Apparatus and methods for bone access and cavity preparation

ABSTRACT

Apparatus and methods for preparing the interior of a bone for therapy. The therapy may include therapy for a bone fracture. The apparatus and methods may involve orienting a surgical instrument for proper deployment in the interior of the bone. An instrument guide may be positioned and retained against translation along, and rotation about one or more of three substantially orthogonal axes. Apparatus placed exterior to the bone may register the guide to a region inside the bone that is designated for preparation or treatment. One or more broaching members may be used to prepare the region for treatment. A broaching member may be expandable inside the bone. A broaching member may be flexible such that it broaches bone having a relatively lower density and it leaves bone having a relatively higher density substantially intact.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a nonprovisional of U.S. Provisional ApplicationsNos. 61/296,722, filed on Jan. 20, 2010, and 61/389,507, filed on Oct.4, 2010, both of which are hereby incorporated by reference in theirentireties.

FIELD OF TECHNOLOGY

Aspects of the disclosure relate to providing apparatus and methods forrepairing bone fractures. In particular, the disclosure relates toapparatus and methods for repairing bone fractures utilizing a devicethat is inserted into a bone.

BACKGROUND

Bone fracture fixation may involve using a structure to counteract orpartially counteract forces on a fractured bone or associated bonefragments. In general, fracture fixation may provide longitudinal (alongthe long axis of the bone), transverse (across the long axis of thebone), and rotational (about the long axis of the bone) stability.Fracture fixation may also preserve normal biologic and healingfunction.

Bone fracture fixation often involves addressing loading conditions,fracture patterns, alignment, compression force, and other factors,which may differ for different types of fractures. For example, midshaftfractures may have ample bone material on either side of the fracture inwhich anchors may be driven. End-bone fractures, especially on thearticular surface may have thin cortical bone, soft cancellous bone, andrelatively fewer possible anchoring locations. Typical bone fracturefixation approaches may involve one or both of: (1) a device that iswithin the skin (internal fixation); and (2) a device that extends outof the skin (external fixation).

Internal fixation approaches typically involve one or both of: (a) aplate that is screwed to the outside of the bone; and (b) an implantthat is inserted inside the bone.

Plates are often characterized by relatively invasive surgery, supportof fractured bone segments from one side outside of bone, and screwsthat anchor into the plate and the bone.

Implants may include intramedullary rods or nails, such as those used inmid shaft treatments. The typical intramedullary rod or nail is fixed indiameter and is introduced into the medullary canal through an incision.Flexible intramedullary rod-like solutions utilize structures that canbe inserted into the medullary cavity through an access site and then bemade rigid. The flexible structures may be reinforced with polymers orcements. Multi-segment fractures, of either the midshaft or end-bone,may require alignment and stability in a manner that generates adequatefixation in multiple directions. Implants may be used to treat midshaftfractures and end-bone fractures.

Implant-based therapies may involve removing bone tissue from theinterior of the bone to prepare the interior for the implant.Preparation for the implant may involve providing a space in the boneinterior for reception of the implant.

Proper location, size, shape, orientation and proximity to bonefragments and anatomical features, among other factors, may increase thetherapeutic effectiveness of the implant.

It would be desirable, therefore, to provide apparatus and methods forpreparation of a bone interior.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects and advantages of the invention will be apparent uponconsideration of the following detailed description, taken inconjunction with the accompanying drawings, in which like referencecharacters refer to like parts throughout, and in which:

FIG. 1 shows illustrative apparatus in accordance with principles of theinvention.

FIG. 2 shows illustrative anatomy in connection with which the inventionmay be practiced.

FIG. 3 shows a view, taken along lines 3-3 (shown in FIG. 1) of aportion of the apparatus shown in FIG. 1.

FIG. 4 shows a view, taken along lines 4-4 (shown in FIG. 1) of aportion of the apparatus shown in FIG. 1.

FIG. 5 shows a view, taken along lines 5-5 (shown in FIG. 1) of aportion of the apparatus shown in FIG. 1.

FIG. 6 shows a portion of the apparatus shown in FIG. 1 along with otherapparatus in accordance with principles of the invention.

FIG. 7 shows a portion of the apparatus shown in FIG. 1 in a state thatis different from the state shown in FIG. 1.

FIG. 8 shows a portion of the apparatus shown in FIG. 1.

FIG. 9 shows a portion of the apparatus shown in FIG. 1 along with otherapparatus in accordance with principles of the invention.

FIG. 10 shows a portion of the apparatus shown in FIG. 1.

FIG. 11 shows other illustrative apparatus in accordance with principlesof the invention.

FIG. 12 shows a partial cross-sectional view, taken along lines 12-12(shown in FIG. 11), of the apparatus shown in FIG. 11.

FIG. 13 shows a partial cross-sectional view, taken along lines 13-13(shown in FIG. 11) of the apparatus shown in FIG. 11.

FIG. 14 shows other illustrative apparatus in accordance with principlesof the invention.

FIG. 15 shows a portion of the apparatus shown in FIG. 14.

FIG. 16 shows a portion (labeled “16”) of the apparatus shown in FIG.11.

FIG. 17 shows a view, taken along lines 17-17 (shown in FIG. 16) of aportion of the apparatus shown in FIG. 16.

FIG. 18 shows a view, taken along lines 18-18 (shown in FIG. 17) of theapparatus shown in FIG. 17.

FIG. 19 shows other illustrative apparatus in accordance with principlesof the invention.

FIG. 20 shows a partial cross-sectional view, taken along lines 20-20(shown in FIG. 7) of the apparatus shown in FIG. 7.

FIG. 21 shows a partial cross-sectional view, taken along lines 21-21(shown in FIG. 8) of the apparatus shown in FIG. 8.

FIG. 22 shows a partial cross-sectional view, taken along lines 22-22(shown in FIG. 21) of the apparatus shown in FIG. 21.

FIG. 22A shows the apparatus shown in FIG. 22 along with illustrativeanatomy in connection with which the invention may be practiced.

FIG. 23 shows a view, taken along lines 23-23 (shown in FIG. 20), of theapparatus shown in FIG. 20.

FIG. 24 shows a partial cross-sectional view, taken along lines 24-24(shown in FIG. 8) of the apparatus shown in FIG. 8.

FIG. 25 shows a portion of the apparatus shown in FIG. 9, along withother apparatus.

FIG. 26 shows a partial cross-sectional view, taken along lines 26-26(shown in FIG. 25), of apparatus shown in FIG. 25.

FIG. 27 shows information that may be used to manufacture apparatus inaccordance with the principles of the invention.

FIG. 28 shows a partial cross-sectional view, taken along lines 28-28(shown in FIG. 25), of apparatus shown in FIG. 25.

FIG. 29 shows a partial cross-sectional view, taken along lines 29-29(shown in FIG. 25), of apparatus shown in FIG. 25.

FIG. 30 shows apparatus shown in FIG. 25 in a state that is differentfrom the state shown in FIG. 25.

FIG. 31 shows still other apparatus in accordance with the principles ofthe invention.

FIG. 32 shows yet other apparatus in accordance with the principles ofthe invention.

FIG. 33 shows yet other apparatus in accordance with the principles ofthe invention.

FIG. 34 shows yet other apparatus in accordance with the principles ofthe invention.

FIG. 35 shows yet other apparatus in accordance with the principles ofthe invention.

FIG. 36 shows yet other apparatus in accordance with the principles ofthe invention.

FIG. 37 shows a portion of the apparatus shown in FIG. 36.

FIG. 38 shows a partial cross-sectional view, taken along lines 38-38(shown in FIG. 37), of the apparatus shown in FIG. 37.

FIG. 39 shows a partial cross-sectional view, taken along lines 39-39(shown in FIG. 37), of the apparatus shown in FIG. 37.

FIG. 40 shows a partial cross-sectional view, taken along lines 40-40(shown in FIG. 37), of the apparatus shown in FIG. 37.

FIG. 41 shows yet other apparatus in accordance with the principles ofthe invention.

FIG. 42 shows yet other apparatus in accordance with the principles ofthe invention.

DETAILED DESCRIPTION OF THE INVENTION

Apparatus and methods for preparing the interior of a bone for therapyare provided. The therapy may include therapy for a bone fracture. Theapparatus and methods may involve orienting a surgical instrument forproper deployment in the interior of the bone. The surgical instrumentmay provide access from outside the bone to the interior of the bone.The surgical instrument may prepare the interior to receive atherapeutic device. The surgical instrument may include a therapeuticdevice.

Apparatus and methods for positioning a surgical instrument relative toexterior features of a bone are provided. The apparatus may be asurgical instrument guide.

The surgical instrument may be a device for repairing the bone. Thesurgical instrument may be a prosthetic device. For example, thesurgical instrument may include one or more of the features of devicesthat are shown and described in U.S. Patent Application Publication No.2009/0182336A1, which is hereby incorporated by reference herein in itsentirety. The surgical instrument may be for accessing an interiorregion of the bone. For example, the surgical instrument may be a bonesaw. The surgical instrument may be a drill. The surgical instrument maybe for preparing the interior region of the bone to receive atherapeutic device. For example, the surgical instrument may be abroach.

The surgical instrument may have a portion that is configured to bepositioned in a targeted region inside the bone.

The bone may have a surface. The surface may have a normal axis. Thenormal axis may be substantially perpendicular to the surface. Thesurface may have an anterior-posterior axis. The anterior-posterior axismay extend in a direction that is substantially normal to the anteriorand posterior sides of the bone. The surface may have a proximal-distalaxis. The proximal-distal axis may extend in a direction that issubstantially along the bone. The bone surface may have curvature. Thecurvature may define a curvature axis. The curvature may becircumferential around the bone. The curvature axis may be parallel ornear parallel with the proximal-distal axis.

The surgical instrument guide may include a bottom index. The bottomindex may provide for aligning the device at a position along thesurface normal axis. The position may be flush with the surface. Thebottom index may be a bottom surface of the device. The bottom index maybe one or more features that project from the bottom surface of thedevice.

The surgical instrument guide may include first and second lateralextensions. The first lateral extension may be configured to respond toan anterior contour of the bone. The anterior contour may be a contouron the anterior side of the bone. The second lateral extension may beconfigured to respond to a posterior contour of the bone. The posteriorcontour may be a contour on the posterior side of the bone. The firstand second lateral extensions may provide for aligning the device alongthe anterior-posterior axis.

The surgical instrument guide may include a distal index. The distalindex may be configured to provide visual alignment along theproximal-distal axis.

In some embodiments, the surgical instrument guide may include a firstbone contactor. The first bone contactor may be configured to engage thesurface. The apparatus may include a second bone contactor. The secondbone contactor may be configured to engage the surface. When the firstand second bone contactors engage the surface, the first and secondcontactors resist rotation about the surface normal axis.

In some embodiments, the first and second bone contactors may beconfigured to penetrate the surface.

In some embodiments, the surgical instrument guide may include first andsecond lateral cleats. The first lateral cleat may be configured toengage an anterior portion of the bone. The second lateral cleat may beconfigured to engage a posterior portion of the bone. When the first andsecond lateral cleats are engaged in the bone, the first and secondlateral cleats may resist rotation about the proximal-distal axis of thebone.

The surgical instrument guide may include an instrument guide member.The surgical instrument guide may include an aligning member. Thealigning member may be configured to align the guide member with thebone. The surgical instrument guide may include a base member. The basemember may support the aligning member.

In some embodiments, the surgical instrument guide may include a lateralcleat. The lateral cleat may be configured to resist movement of thebase member in a direction along the circumference of the elongatedbone. The lateral cleat may include a stem that is directly fixed to thebase.

In some embodiments, the surgical instrument guide may include a bonecontactor. The bone contactor may be configured to resist rotation ofthe base about an axis that is substantially normal to the surface.

In some embodiments, the bone contactor may be a first bone contactorand the surgical instrument guide may include a second bone contactor.The first and second bone contactors may extend from a surface of thebase. The first and second bone contactors may be configured to contactthe bone surface along the curvature axis of the bone surface.

In some embodiments, the surgical instrument guide may include a handlesupport and a grip. The grip may be rotatable relative to the handlesupport when a torque greater than a threshold torque is applied to thegrip.

In some embodiments, the surgical instrument guide may include analignment template. The alignment template may be configured to registerthe instrument guide member to a target region inside the bone.

In some embodiments, the instrument template may include a dimensionthat corresponds to a dimension of a surgical instrument that isconfigured for deployment in the bone interior through the instrumentguide member.

In some embodiments, the template may include a fluoroscopicallydetectable material.

In some embodiments, the template may be fixed to the base. The templatemay map to a lateral view plane in the cavity.

In some embodiments, the template may map to an anterior-posterior viewplane in the cavity.

In some embodiments, the surgical instrument guide may include a firsttemplate that maps to the lateral view plane and a second template thatmaps to the anterior-posterior view plane.

In some embodiments, the surgical instrument guide may include achannel. The channel may be configured to direct an elongated fixationmember into the bone. The elongated fixation member may be a wire. Thewire may be a k-wire. The elongated fixation member may be a rod. Therod may be a threaded rod.

In some embodiments, the surgical instrument guide may include a firstchannel and a second channel. The first and second channels may beconfigured to direct first and second elongated fixation members intothe bone.

In some embodiments, the first and second channels may be oblique toeach other.

The methods may include a method for performing a procedure in a boneinterior. The method may include positioning an instrument templateoutside the bone interior at a position that corresponds to a targetregion inside the bone. The method may include generating an electronicimage showing the instrument template and the target region. The methodmay include delivering an instrument to the target region.

In some embodiments, the delivering may include arranging a guide memberto direct the instrument to the target region. The guide member may havea fixed orientation relative to the instrument template.

In some embodiments, the positioning may include positioning a coringsaw outline.

In some embodiments, the positioning may include positioning a broachoutline.

In some embodiments, the positioning may include positioning aprosthesis outline.

In some embodiments, the positioning may include positioning a boneimplant outline.

In some embodiments, the generating may include receiving an image usingfluoroscopy.

In some embodiments, the instrument template may be a first instrumenttemplate and the method may include positioning a second instrumenttemplate outside the bone interior at a position that corresponds to thetarget region; and generating an electronic image showing the secondinstrument template and the target region.

In some embodiments, the positioning of a second instrument template mayinclude arranging the second instrument template in a plane that isoblique to a plane that includes the first instrument template.

In some embodiments, the positioning of the second instrument templatecomprises arranging the second instrument template in a plane that issubstantially orthogonal to a plane that includes the first instrumenttemplate.

In some embodiments, the delivering may include delivering a coring saw.

In some embodiments, the delivering may include delivering a boneinterior broach.

In some embodiments, the delivering may include delivering a prosthesis.

The methods may include a method for guiding an instrument into a boneinterior. The method may include positioning an instrument guideadjacent a bone. The instrument guide may include a first fixationelement and a second fixation element.

The method may include passing a first fixation member through the bonesuch that the first fixation member is in contact with the firstfixation element. The method may include passing a second fixationmember through the bone such that the second fixation member is incontact with the second fixation element.

In some embodiments, the passing of a second fixation member may includeorienting the second fixation member substantially obliquely withrespect to the first fixation member.

In some embodiments, the passing of the second fixation member mayinclude encompassing human tissue in a region defined by the firstfixation member, the second fixation member and the instrument guidesuch that the instrument guide is retained adjacent the bone by thehuman tissue.

Apparatus and methods for guiding an instrument relative to an elongatedbone are provided. The apparatus may be a surgical instrument guide.

The bone may have a longitudinal axis.

The surgical instrument guide may include an instrument guide member anda base member. The base member may support the guide member. Theinstrument guide member may be configured to pivot with respect to thebase member from a first position to a second position. The firstposition may define a first angle relative to the bone longitudinalaxis. The second position may define a second relative to the bonelongitudinal axis.

In some embodiments, the surgical instrument guide may include analignment template. The alignment template may register the instrumentguide member to a first target region inside the bone when the guidemember is in the first position. The alignment template may register theinstrument guide member to a second target region inside the bone whenthe guide member is in the second position.

In some embodiments, the template may have a dimension that correspondsto a dimension of a surgical instrument that is configured fordeployment in the bone interior through the instrument guide member.

In some embodiments, the template may include a fluoroscopicallydetectable material.

In some embodiments, the template may be fixed to the guide member. Thetemplate may map to a lateral plane in the bone interior. The templatemay map to an anterior plane in the cavity. The template may map to aposterior plane in the cavity.

In some embodiments, the template may be a first template and thesurgical instrument guide may include a second template. The secondtemplate may be fixed to the guide member. The second template may mapto a lateral plane in the cavity.

In some embodiments, the surgical instrument guide may include a guidemember stop. The guide member stop may be configured to fix the positionof the guide member with respect to the base member.

In some embodiments, the stop may induce a frictional force between afirst surface on the guide member and a second surface on the basemember.

In some embodiments, the stop may include a projection that interfereswith relative movement between the guide member and the base.

The methods may include a method for introducing an instrument into aninterior of a bone. The method may include introducing the instrumentinto a guide member that is pivotably mounted on a base. The base may bepositioned adjacent a bone. The method may include pivoting the guidemember relative to the base to change an angle between the guide memberand the base. The method may include advancing the instrument throughthe guide member.

In some embodiments, the pivoting may include adjusting the angle toalign an instrument template with a target region inside the interior ofthe bone.

In some embodiments, the adjusting may include viewing an electronicimage that shows the instrument template and the target region.

In some embodiments, the method may include fixing the angle between theguide member and the base.

Apparatus and methods for broaching an interior region of a bone areprovided. The bone may include first bone material. The first bonematerial may include cancellous bone. The bone may include second bonematerial. The second bone material may include cortical bone. The secondbone material may have a density that is higher than a density of thefirst bone material.

The apparatus may include rotator. The apparatus may include a broachingmember.

The broaching member may be moved in the bone interior to displace,disaggregate, disintegrate, dislocate, excavate, abrade, cut orotherwise broach bone material. The broaching member may be rotated inthe bone interior. The rotation may be continuous. The rotation may bepulsed. The rotation may be unidirectional. The rotation may alternatebetween a first rotational direction and a second rotational direction.

The broaching member may be fixed to the rotator. The broaching membermay be configured to be moved relative to the rotator to displace bonematerial that is radially away from the rotator.

In some embodiments, the broaching member may be configured tosubstantially deflect around second bone material.

In some embodiments, the broaching member may be configured to form inthe bone a space having a first contour that corresponds to a shape ofthe broaching member. The broaching member may be configured to form inthe bone a space having a second contour that corresponds to anatomythat includes the second bone material. The broaching member may be afirst broaching member and the apparatus may include a second broachingmember. The second broaching member may be disposed opposite the firstbroaching member.

In some embodiments, the broaching member may include a cutting edge.

In some embodiments, the broaching member may include a flexible wiresegment. The wire segment may include braided wire.

In some embodiments, the apparatus may include a reinforcement thatsupports the broaching member. The reinforcement may support a cuttingedge.

In some embodiments, the broaching member may have a proximal end thatis fixed to the rotator and a distal end that is fixed to the rotator.

In some embodiments, the broaching member may have a proximal end thatis fixed to the rotator and a distal end that is free.

In some embodiments, the broaching member may include an edge of an opencell in a mesh.

The broaching member may include a segment that has any suitable form.For example, the segment may be straight, circular, rhombic, square,triangular, oval, ellipsoid, spiral, loop-shaped, hoop-shaped,teardrop-shaped, egg-beater-shaped, football-shaped, or any othersuitable shape. The segment may be a closed loop. The loop may beasymmetric.

The segment may have one or more of a variety of transverse crosssections, such as square, rectangular, octagonal, contours with sharpedges, stranded cable, or other suitable configurations to facilitatebone displacement.

The segment may have a leading edge. The leading edge may be beveled ata suitable angle, including an angle from about 5° to about 75°. Theangle may cause leading edge 2202 to be generally sharp or knife-like.

The segment may be rigid. The segment may be resilient.

The broaching member may have one or more ends that are attached toapparatus such as a drive shaft or a suitable support, such as a hub.The broaching member may have a free end. Broaching members with freedistal ends may have any suitable shape at the tine distal ends, such aspointed, forked, rounded, blunt or truncated.

The broaching member may have an end that is attached to apparatus bycrimping, welding, set-screw, snap fit or any other suitable fastening.The broaching member may have one or more ends that are of unitaryconstruction with the apparatus.

The broaching member may include a tine. The tine may be resilient orstiff. The tine may have an end that is attached to a drive shaft. Thetine may have a free end.

The broaching member may include a blade.

The broaching member may include numerous interconnected cells. Thecells may be arranged in a network. The cells may be linked such thatwhen the structure is stressed (e.g., compressed) at a point the stressis distributed to nearby cells. The cells may be constructed fromlaser-cut tube stock that is expanded into a suitable shape.

The broaching member may be one of a number of broaching members in abroaching head. For example, the broaching head may have one broachingmember, 2-6 broaching members, 7-20 broaching members, more than 20broaching members, 100 broaching members or any suitable number ofbroaching members.

When a large number (i.e., when the circumferential density of broachingmembers is relatively high) of broaching members are present during therotation of a broaching head, a relatively lower torque may be requiredto drive the broaching head.

Broaching member may rotate in a bone cavity that has an irregularshape, for example, nonround, oblong, or angular. The cavity may besmaller than a diameter of broaching member.

Broaching member may include any suitable structural form such as wire,ribbon, cable, stranded wire, braided wire, braided ribbon, or any othersuitable structural form.

Broaching member may include any suitable material, such as polymer,metal, composite, stainless steel, Nitinol (shapeset, superelastic orother Nitinol), other alloy or any other suitable material.

The broaching member may be supported by one or more reinforcements.

The reinforcement may be sized and positioned to support a segment ofthe broaching member in a desired contour. The reinforcement may providebone-broaching abrasiveness, momentum or both.

The reinforcement may be a tube.

The reinforcement may be a brace. The brace may be fixed to thebroaching member, for example, by crimping, welding or press-fit. Thebrace may include broaching edges for displacing bone material. Thebroaching edges may have any suitable form, such as serrated, saw-tooth,knife-edge, rectilinear edge or any other suitable form.

The reinforcement may be formed from polymer, metal, alloy or any othersuitable material.

The reinforcement may be formed from a pattern that is cut into a metaltube.

In some embodiments, the apparatus may include a distal hub. Thebroaching member may have a distal end that is fixed to the distal hub.The distal hub may be configured to move between a first position and asecond position. The first and second positions may be located along alongitudinal axis of the rotator.

The distal hub may be constructed of metal, stainless steel, laser-cuttube, polymer, ceramic or any other suitable material.

The distal hub may include flutes. The distal hub may include broachingedges.

The methods may include a method for broaching an interior region of abone. The interior region may include a bottom surface. The bottomsurface may be an surface of a portion of the bone that is opposite anaccess hole in the bone.

The method may include expanding a bone broaching member in the interiorregion. The method may include disaggregating relatively low-densitymaterial inside the bone using the member. The method may includedeflecting the broaching member away from relatively high-densitymaterial inside the bone.

In some embodiments, the method may include rotating the bone broachingmember using a flexible drive shaft.

In some embodiments, the method may include changing the elevation ofthe bone broaching member relative to the bottom surface.

In some embodiments, the disaggregating may include cutting therelatively low-density material.

In some embodiments, the disaggregating may include displacing therelatively low-density material.

In some embodiments, the method may include registering an exteriorinstrument guide to the bone broaching member; visually mapping theexterior instrument guide to the interior region; and deploying the bonebroaching member to the interior region based on the exterior instrumentguide. The exterior instrument guide may be exterior to the bone.

Apparatus and methods for treating a bone interior are provided.

The apparatus may include a flexible sheath. The flexible sheath mayinclude stress-relief features that allow bending under tension andcompression. The stress-relief features may include slots or slotpatterns. The stress-relief features may be provided usinglaser-cutting.

The stress-relief features may include sintered particles. The particlesmay include metal, polymer, composite or any other suitable material.

The flexible sheath may have a first configuration and a secondconfiguration. The second configuration may have a smaller radius ofcurvature than the first configuration. The apparatus may include arotatable shaft. The rotatable shaft may extend through the sheath. Theapparatus may include an elongated steering member. The elongatedsteering member may be configured to deflect the flexible sheath fromthe first configuration to the second configuration.

In some embodiments, the elongated steering member may be configured tobe elastically deformed when the elongated steering member deflects theflexible sheath from the first configuration to the secondconfiguration.

In some embodiments, the elongated steering member may include a firstportion. The first portion may translate along a longitudinal directionof the sheath. The elongated steering member may include a secondportion. The second portion may be configured to extend radially outwardthrough a passage in the sheath when the elongated steering memberdeflects the flexible sheath from the first configuration to the secondconfiguration.

In some embodiments, the rotatable shaft may have a distal end and theapparatus may include an expandable head that extends from the distalend. The expandable head may include a compressed configuration fortranslating within the sheath. The expandable head may include anexpanded configuration when the expandable head is deployed outside thesheath.

In some embodiments, the expandable head may be configured to displacecancellous bone and not cortical bone.

Apparatus and methods for preparation of the interior of a bone areprovided.

The apparatus may include an elongated member. The elongated member mayhave a longitudinal axis. The elongated member may be curved about thelongitudinal axis. The elongated member may be configured to rotateabout the longitudinal axis inside the bone.

In some embodiments, the elongated member may include a substantiallyspiral segment. The spiral segment may include a proximal end and adistal end. The proximal end may be disposed at a first radius from thelongitudinal axis. The distal end may be disposed at a second radiusfrom the longitudinal axis. The second radius may be at least as greatas the first radius. The second radius may be greater than the firstradius.

In some embodiments, the elongated member may be a first elongatedmember and the apparatus may include a second elongated member. Thesecond elongated member may be curved about the longitudinal axis. Thesecond elongated member may be configured to rotate about thelongitudinal axis.

In some embodiments, the second elongated member may include asubstantially spiral second segment.

In some embodiments, the proximal end may be a first proximal end andthe distal end may be a first distal end. The spiral second segment mayinclude a second proximal end and a second distal end. The secondproximal end may be disposed at a third radius from the longitudinalaxis. The second distal end may be disposed at a fourth radius from thelongitudinal axis. The fourth radius may be at least as great as thethird radius. The fourth radius may be greater than the third radius.

In some embodiments, the third radius may be substantially the same asthe first radius; and the fourth radius may be substantially the same asthe second radius.

In some embodiments, the apparatus may include a circumferential offset.The circumferential offset may be in a circumferential direction aboutthe longitudinal axis. The circumferential offset may be between thesecond proximal end and the first proximal end. The circumferentialoffset may be between the second distal end and the first distal end.

In some embodiments, the apparatus may include a support. The supportmay include a proximal support end. The proximal support end may befixed to a shaft. The apparatus may include a support segment. Thesupport segment may be fixed to at least one of the first and secondspiral segments. The support segment may conform to a contour of thespiral segment.

The methods may include a method for preparing a bone interior. Themethod may include providing access to a bone intramedullary space. Themethod may include introducing into the intramedullary space anelongated member. The elongated member may have a substantially spiralsegment. The spiral segment may have a longitudinal axis. The method mayinclude rotating the substantially spiral segment about the longitudinalaxis to displace cancellous bone matter.

In some embodiments, the elongated member may be a first elongatedmember, the substantially spiral segment may be a first substantiallyspiral segment, and the method may include introducing into theintramedullary space a second elongated member. The second elongatedmember may have a substantially spiral second segment. The substantiallyspiral second segment may share the longitudinal axis with the firstsubstantially spiral segment. The method may include rotating thesubstantially spiral second segment about the longitudinal axis.

In some embodiments, the first spiral segment may have a first periodicrotation cycle. The second spiral segment may have a second periodicrotation cycle. The second periodic rotation cycle may lag behind thefirst periodic rotation cycle by a phase lag. The phase lag may be aboutPi radians.

Apparatus and methods for sawing a hole in a bone are provided. The bonemay have a longitudinal bone axis.

The apparatus may include a bone coring saw. The bone coring saw mayinclude a tooth. The tooth may include a first cutting member and asecond cutting member. The first cutting member may be configured to cutbone when the coring saw rotates in a first direction. The secondcutting member may be configured to cut bone when the coring saw rotatesin a second direction. The second direction may be rotationally oppositefrom the first direction.

The bone coring saw may include a cylindrical tube. The cylindrical tubemay define a tube longitudinal direction and a tube radial direction.The bone coring saw may include a saw tooth. The saw tooth may extendlongitudinally from an end of the cylindrical tube. The saw tooth mayinclude a cutting surface that is oblique to the tube radial direction.

The methods may include a method for sawing a hole in the bone. Themethod may include forming a substantially cylindrical passage into theintramedullary space of a bone. The substantially cylindrical passagemay extend along a direction that is at an acute angle to thelongitudinal bone axis. The method may include removing from the bone asubstantially cylindrical plug that is substantially coaxial with thepassage.

In some embodiments, the forming may include tunneling through the boneusing a K-wire.

In some embodiments, the removing may include sawing a hole using arotary coring saw.

In some embodiments, the method may include rotating the rotary coringsaw about a portion of the K-wire.

In some embodiments, the method may include sustaining a coaxialrelationship between the K-wire and the rotary coring saw. Thesustaining may include rotating the rotary coring saw about a bushing.The K-wire, the bushing and the rotary coring saw may be substantiallycoaxial.

In some embodiments, the method may include translating the K-wirerelative to the rotary coring saw to remove from the coring saw thecylindrical plug.

The method may include a method for providing access to anintramedullary space of a bone. The method may include supporting acylindrical body of a rotary saw at an acute angle to a surface of thebone; and engaging teeth of the rotary saw with the surface.

Apparatus and methods for accessing the inside of a bone are provided.

The apparatus may include a rotatable saw that includes a cannula. Theapparatus may include a bushing that is disposed in the cannula. Theapparatus may include a wire that is disposed substantially coaxiallywith the rotatable saw in the bushing.

In some embodiments, the wire may include a distal end that isconfigured to penetrate the bone. The wire may include a proximal endthat is configured to receive torque.

In some embodiments, the wire may be configured to drill a pilot hole inthe bone. The pilot hole may have an axis that forms an acute angle witha surface of the bone at the opening of the pilot hole. The saw mayinclude teeth.

The teeth may be arranged adjacent a distal end of the cannula. Thebushing may be configured to align the rotatable saw coaxially with theaxis when the teeth contact the bone.

In some embodiments, the apparatus may include a biased member proximalthe bushing. The biased member may be configured to urge a distal end ofthe bushing toward the bone when the teeth have penetrated into thebone.

In some embodiments, the bushing may be fitted into the cannula with atolerance that provides friction between the bushing and the rotatablesaw. The friction may resist proximally-directed force from a bone corein the cannula while the teeth are cutting into the bone.

In some embodiments, the rotatable saw may include a cylindrical bodyhaving a wall thickness that is traversed by a vent. The vent may beconfigured to exhaust bone matter.

In some embodiments, the wire may include a distal diameter and aproximal diameter. The proximal diameter may be greater than the distaldiameter. The wire may include a shoulder where the distal diameteradjoins the proximal diameter. The shoulder may be configured to betranslated proximally relative to the rotatable saw to eject a bone corefrom the cannula.

The apparatus may include an assembly for accessing the inside of abone.

The assembly may include an arrangement of teeth. The teeth may besupported at the end of a rotatable frame. The frame may define one ormore passageways. The passageways may extend from a cannula inside theframe to a region that is outside the frame.

In some embodiments, the assembly may include a bushing. The bushing maybe disposed in the cannula. The assembly may include a wire. The wiremay be disposed substantially coaxially with the rotatable saw in thebushing.

In some embodiments, the wire may be configured to drill a pilot hole inthe bone. The pilot hole may have an axis that forms an acute angle witha surface of the bone at the opening of the pilot hole. The busing maybe configured to align the rotatable saw coaxially with the axis whenthe teeth contact the bone.

Apparatus and methods for preparing a bone interior are provided. Theapparatus may have a longitudinal apparatus axis.

The apparatus may include one or more broaching members. The broachingmembers may be blades. A first blade may be linked to a second blade bya linkage. The linkage may be configured to be rotated about thelongitudinal axis. The linkage maybe configured to be radially displacedfrom the longitudinal apparatus axis.

In some embodiments, at least one of the first and second blades may berigid.

In some embodiments, at least one of the first and second blades mayinclude stainless steel.

In some embodiments, at least one of the first and second blades mayinclude Nitinol.

In some embodiments, the linkage may include a pin.

In some embodiments, the linkage may be a first linkage. The apparatusmay include an actuator. The actuator may be linked to the first bladeby a second linkage. The actuator may be linked to the second blade by athird linkage. The actuator may include a main body. The main body mayinclude members that are configured to be displaced relative to eachother. One of the members may be fixed relative to the main body.

In some embodiments, at least one of the second and third linkages mayinclude a pin.

In some embodiments, the third linkage is distal the second linkage.

In some embodiments, the actuator may be configured to radially displacethe first linkage by changing a distance between the second linkage andthe third linkage.

In some embodiments, the actuator may include a first elongated actuatormember. The first elongated actuator member may be linked to the secondlinkage. The actuator may include a second elongated actuator member.The second elongated actuator member may be linked to the third linkage.The second elongated actuator member may be configured to radiallydisplace the first linkage by changing a longitudinal offset between thefirst and second elongated members.

In some embodiments, the apparatus may be configured to traverse a pathin the bone interior. The apparatus may include a fourth linkage thatconstrains the longitudinal offset based on position of the apparatusalong the path.

In some embodiments, the fourth linkage may be a manual linkage.

In some embodiments, the longitudinal offset may include a range ofvalues. The range of values may include a first value. The first valuemay correspond to a first linkage first radial displacement. The rangeof values may include a second value. The second value may correspond toa first linkage second radial displacement. The second radialdisplacement may be greater than the first radial displacement.

In some embodiments, the range may include a third value. The thirdvalue may correspond to a first linkage third radial displacement. Thefirst linkage third radial displacement may be less than the secondradial displacement.

In some embodiments, the apparatus may include a cutting surface. Thecutting surface may be disposed on one of the first and second blades.At the first and third radial displacements, the cutting surface may bedisengaged from the bone.

In some embodiments, at the second radial displacement, the cuttingsurface may be engaged with the bone.

In some embodiments, the first blade may have a first bound portion. Thefirst bound portion may be between the first and second linkages. Thefirst blade may have a first free portion. The first free portion mayextend beyond the first linkage in a direction away from the secondlinkage.

In some embodiments, the second blade may have a second bound portion.The second bound portion may be between the first and third linkages.The second blade may have a second free portion. The second free portionmay extend beyond the first linkage in a direction away from the thirdlinkage.

In some embodiments, the first bound portion may be longer than thesecond bound portion.

In some embodiments, the second bound portion may be longer than thefirst bound portion.

In some embodiments, the first free portion may be longer than thesecond free portion.

In some embodiments, the second free portion may be longer than thefirst free portion.

In some embodiments, the apparatus may include a cutting surface. Thecutting surface may be disposed on at least one of the first and secondblades. The fourth linkage may be programmed to position the cuttingsurfaces at different radial displacements along the path. Each of theradial displacements may correspond to a longitudinal position on thepath.

In some embodiments, the fourth linkage may control the longitudinaloffset based on an electronic signal. The electronic signal may be basedon a set of digital instructions. The digital instructions may be basedon a digitized image of the bone interior.

In some embodiments, the apparatus may include a third blade. Theapparatus may include a fourth blade. The third blade may be linked tothe fourth blade by a fourth linkage. The fourth linkage may beconfigured to be rotated about the longitudinal axis. The fourth linkagemay be configured to be radially displaced from the longitudinal axis.The actuator may be configured to radially displace the fourth linkageby changing the longitudinal offset between the first and secondelongate members.

The methods may include a method for preparing the bone interior. Themethod may include rotating a cutting surface inside a bone about arotational axis. The method may include moving a control member from afirst control position to a second control position.

The cutting surface may be configured to occupy a first radial positionthat corresponds to the first control position. The cutting surface maybe configured to occupy a second radial position that corresponds to thesecond control position. The cutting surface may be configured to occupya third radial position that corresponds to an intermediate controlposition. The intermediate control position may be between the first andsecond control positions. The third radial position may be at a greaterradial distance from the rotational axis than are both the first andsecond radial positions.

In some embodiments, the first and second radial positions may be atsubstantially the same distance from the rotational axis.

In some embodiments, when the cutting surface is at one or both of thefirst and second radial positions, the cutting surface may be disengagedfrom the bone. When the cutting surface is at the third radial position,the cutting surface may be engaged with the bone.

Apparatus and methods for positioning a bone fragment are provided.

The apparatus may include a probe support. The probe support may have aproximal end and a distal end. The apparatus may include a handle. Thehandle may be attached to the proximal end. The apparatus may include aprobe. The probe may be attached to the distal end. The probe supportmay be configured to traverse an angled access hole in a metaphysealbone surface. The probe support may be configured to provide mechanicalcommunication between the handle and the probe when the handle isoutside a bone interior and the probe is inside the bone interior.

In some embodiments, the probe may have a conical tip.

In some embodiments, the probe may have a rounded tip.

In some embodiments, the probe support may include a proximal segmentand a distal segment. The proximal segment may extend from the handle.The distal segment may support the probe.

In some embodiments, the proximal and distal segments may define anobtuse angle.

In some embodiments, the proximal segment may have a first flexibility.The distal segment may have a second flexibility. The second flexibilitymay be greater than the first flexibility.

In some embodiments, the apparatus may include an intermediate segment.The intermediate segment may be between the proximal and distalsegments. The intermediate segment may include a curve.

In some embodiments, the proximal segment may have a first flexibility.The intermediate segment may have a second flexibility. The distalsegment may have a third flexibility. The second flexibility may begreater than the third flexibility.

The methods may include a method for treating a bone. The bone may havea longitudinal bone axis. The method may include providing a hole in thebone. The hole may be at an angle to the longitudinal bone axis. Thehole may provide access to a bone interior region. The method mayinclude advancing a probe through the hole and into the interior region.The method may include displacing cancellous bone using the probe.

In some embodiments, the displacing may include identifying a spatialdistribution of low-density matter in the interior region.

In some embodiments, the method may include displaying an image of theinterior region and the probe when the probe is inside the interiorregion.

The methods may include another method for treating the bone. The methodmay include providing a hole in the bone. The hole may be at an angle tothe longitudinal bone axis. The hole may provide access to a boneinterior region. The method may include advancing a probe through thehole and into the interior region. The method may include displacingbone matter using the probe.

In some embodiments, the displacing may include identifying a spatialdistribution of cancellous bone in the interior region.

In some embodiments, the method may include displaying an image of theinterior region and the probe when the probe is inside the interiorregion.

In some embodiments, the displacing may include positioning a firstcortical bone fragment relative to a second cortical bone fragment.

In some embodiments, the method may include displaying an image of theinterior region and the probe when the probe is inside the interiorregion.

Apparatus and methods in accordance with the invention will be describedin connection with the FIGS. The FIGS. show illustrative features ofapparatus and methods in accordance with the principles of theinvention. The features are illustrated in the context of selectedembodiments. It will be understood that features shown in connectionwith one of the embodiments may be practiced in accordance with theprinciples of the invention along with features shown in connection withanother of the embodiments.

Apparatus and methods described herein are illustrative. Apparatus andmethods of the invention may involve some or all of the features of theillustrative apparatus and/or some or all of the steps of theillustrative methods. The steps of the methods may be performed in anorder other than the order shown or described herein. Some embodimentsmay omit steps shown or described in connection with the illustrativemethods. Some embodiments may include steps that are not shown ordescribed in connection with the illustrative methods.

Illustrative embodiments will now be described with reference to theaccompanying drawings, which form a part hereof.

The apparatus and methods of the invention will be described inconnection with embodiments and features of an illustrative bone repairdevice and associated hardware and instrumentation. The device andassociated hardware and instruments will be described now with referenceto the FIGS. It is to be understood that other embodiments may beutilized and structural, functional and procedural modifications may bemade without departing from the scope and spirit of the presentinvention.

FIG. 1 shows illustrative instrument guide 100 positioned at site H′ onbone B. Broach head 124 may be delivered through guide 100 to targetregion R_(t) of intramedullary space IS. Target region R_(t) isillustrated as being within cancellous bone B_(CA), but could be ineither, or both, of cancellous bone B_(CA) and cortical bone B_(CO).Side template 130 and top template 132 are registered to guide tube 120.Arm 131 may support template 130. A practitioner may position templates130 and 132 such that templates 130 and 132 “project” onto target regionR_(t) so that guide 100 will guide broach head 124 to target regionR_(t).

Template 130 may include lobe outline 134 and shaft outline 136 forprojecting, respectively, a “swept-out” area of broach head 124 and alocation of shaft-like structure 125. Template 132 may include lobeoutline 138 and shaft outline 140 for projecting, respectively, a target“swept-out” area of broach head 124 and a target location of shaft-likestructure 125. Templates 130 and 132 may be configured to project ashape of any suitable instrument that may be deployed, such as a drill,a coring saw, a prosthetic device or any other suitable instrument.

Fluoroscopic imaging may be used to position templates 130 and 132relative to target region R_(t).

Broach head 124 may rotate in intramedullary space IS to clearintramedullary bone matter so that a prosthetic device may be implanted.Broach head 124 may be driven and supported by broach control 126 andbroach sheath 127.

Guide 100 may include base 102. Alignment members 104 and 106 (shown inFIG. 10) may extend from base 102 to align guide centerline CL_(G) ofguide 100 with bone centerline CL_(BS) of the top surface of bone B. Oneor both of alignment members 104 and 106 may be resilient. One or bothof alignment members 104 and 106 may be stiff.

Alignment members 104 and 106 may be relatively free to slide alongsurfaces of bone B. Guide 100 may include contacts 108 and 110 (shown inFIG. 10) that may engage bone B along centerline CL_(BS). Contacts 108and 110 may extend from a bottom surface (shown in FIG. 10) of guide100. Contacts 108 and 110 may prevent guide centerline CL_(G) fromrotating out of alignment with bone centerline CL_(BS).

Contacts 108 and 110 may assure alignment of guide 100 with the surfaceof bone B, because two points of contact may be stable on an unevensurface even in circumstances in which 3, 4 or more contacts are notstable.

Guide 100 may include lateral cleats 112 and 114 (shown in FIG. 10).Lateral cleats 112 and 114 may engage the surface of bone B to preventguide 100 from rotating in direction θ about guide centerline CL_(G).Lateral cleats 112 and 114 may be resilient to allow some sliding overbone B.

When a practitioner positions guide 100 on bone B, alignment members 104and 106 may be the first components of guide 100 to engage bone B.Alignment members 104 and 106 may bring guide centerline CL_(G) intoalignment with bone centerline CL_(BS) before contacts 108 and 110 andcleats 112 and 114 engage bone B. Then, in some embodiments, cleats 112and 114 may engage bone B to inhibit rotation in direction θ. Then, insome embodiments, contacts 108 and 110 may engage bone B along bonecenterline CL_(BS). Contacts 108 and 110 may have sharp points toprovide further resistance to de-alignment of guide centerline CL_(G)from bone centerline CL_(BS). In some embodiments, there may be no morethan two contacts (e.g., 108 and 110) to ensure that the contacts are inline with bone centerline CL_(BS).

Guide 100 may include stem 116 and grip 118. A practitioner may manuallygrip grip 118. In some embodiments, a torque-limiter (not shown) may beprovided to limit the torque that the practitioner can apply via grip118 to contacts 108 and 110.

Guide tube 120 may receive and guide any suitable instrument. Guide tube120 may be oriented at angle α with respect to handle 116. In someembodiments, angle α may be fixed. In some embodiments, angle α may beadjustable. In some embodiments, templates 130 and 132 may be fixedrelative to guide tube 120. In some embodiments, including someembodiments in which α is adjustable and some in which α is notadjustable, guide tube 120 may be oriented so that the axis L_(GT) ofguide tube 120 intersects bone B at substantially the same point as doesaxis L_(H) of stem 116. Grip 118 will thus be positioned directly overthe center of hole site H′.

Guide 100 may include channels 142 and 144 (shown in FIG. 5). Rods 146and 148 may be inserted through channels 142 and 144, respectively,through cortical bone B_(CO). Rods 146 and 148 may stabilize guide 100on bone B. Rods 146 and 148 may be K-wires. Rods 146 and 148 may beinserted using a wire drill.

FIG. 2 illustrates anatomical features of fractured bone B. Referenceframe 200 shows that the view of bone B is substantially inanterior/posterior plane 200. Lateral plane 204 includes volarhalf-plane VOL and dorsal half-plane DOR.

Bone B is illustrated as a radius that is fractured at fractures F_(h)and F_(a) Bone B includes bone portions P_(b), P_(h) and P_(a) in distalend D. Bone segment P_(b) is the largest portion of bone B. Bone segmentP_(h) is a head portion of bone B. Bone segments P_(h) and P_(a) includearticular surface AS. Bone portions P_(b), P_(h) and P_(a) are separatedor partially separated along fractures F_(a) and F_(h). Fracture F_(a)transects articular surface AS. Fracture F_(h) transects head of bone B.

Bone B, shown in a cross section that includes approximate longitudinalaxis L_(B), includes cortical bone B_(CO) and cancellous bone B_(CA).Deployment of an implant into distal end D of bone B may require anaccess hole at site H′. Deployment of the implant may requiredisplacement of cancellous bone B_(CA). Illustrative contours C₁, C₂ andC₃ in cancellous bone B_(CA) are different contours within whichcancellous bone B_(CA) may be displaced. Contour C₄, which is aprojection of contour C₃ onto articular surface AS, shows that contourC₄, for example, may be asymmetric. For example, contour C₄ may havemajor axis A₁ and minor axis A₂ (shown in half). The other contours mayalso be asymmetric.

Apparatus and methods provided herein may provide an access hole H atsite H′. An apparatus inserted at site H′ through access hole H, maytravel a distance x_(H) through intermedullary space IS to reach a headportion of bone B. An apparatus inserted at site I′ through access holeI may travel a distance x_(I) through intermedullary space IS to reach ahead portion of bone B. An apparatus inserted at H′ may require a “bend”to travel through intermedullary space IS to reach a head portion ofbone B. An apparatus inserted at I′ may not require a “bend” to reach ahead portion of bone B. Apparatus and methods provided herein maydisplace cancellous bone B_(CA) within a contour such as C₁, C₂ or C₃.

FIG. 3 shows guide 100, from the side, positioned at site H′ at which anaccess hole is to be provided. Template 130 is positioned to registerwith target area R_(t) a broach (with outline 134) and a drill (withoutline 136). Template 132 extends normal to the plane of FIG. 3.Fluoroscopy may be used to select the target area based on contours ofcancellous bone B_(CA) and cortical bone B_(CO) (shown in FIG. 2) inbone B. A rod such as a K-wire may be inserted through hole 302 and boneB to fix a position of guide 100 relative to bone B.

FIG. 4 shows guide 100, from the top, positioned at site H′ (not shown).Template 132 is positioned to register with target area R_(t) the broach(with outline 138) and the drill (with outline 140).

Template 132 extends from the base of grip 118.

Arm 404 supports template 130, which extends normal to the plane of FIG.3. Fluoroscopy may be used to select the target area based on contoursof cancellous bone B_(CA) (shown in FIG. 2) and cortical bone B_(CO)(shown in FIG. 2) in bone B. A rod such as a K-wire may be insertedthrough hole 402 and bone B to fix a position of guide 100 relative tobone B.

Cannula 406 is present in guide tube 120 for delivering instruments tointramedullary space IS (shown in FIG. 2) of bone B.

FIG. 5 shows guide 100, from above and posterior, positioned at site H′.H′ is approximately centered along axis L_(GT) of guide tube 120. Distalends of rods 146 and 148 penetrate bone B to maintain a position ofguide 100. Rods 146 and 148 may be at oblique to each other. Rods 146and 148 may be skewed relative to each other.

FIG. 6 shows illustrative drill 600 inserted in guide tube 120 andpenetrating bone B. Drill 600 may penetrate cortical bone B_(CO) (shownin FIG. 2) and cancellous bone B_(CA) (shown in FIG. 2). Drill 600 mayinclude teeth 602, flutes 604, shaft 606, torque adapter 608 and anyother suitable features. Torque adapter 608 may be an A-O type torqueadapter or any other suitable torque adapter. Stop 610 may be present tolimit penetration depth dp of drill 600. Stop 610 may be any suitablefeature that limits forward axial motion of members 600. Stop 610 mayinclude annular distal surface 612, which may abut rim 614 of guide tube120 when d_(P) is reached. Fastener 616, which may be a set screw, maybe used to fix the position of stop 610 along shaft 606 to fix themagnitude of d_(P).

FIG. 7 shows illustrative intramedullary broach 700. Broach 700 mayinclude broach head 702. Broach head 702 may include illustrativebroaching member 704.

Broaching member 704 may be sufficiently rigid to displace cancellousbone B_(CA). Broaching member 704 may be sufficiently flexible to bedeformed by cortical bone B_(CO). In some embodiments, broaching member704 may be expandable. Broach head 702 may be supported by and rotatedby shaft assembly 714. Broach control 706 may include drive handle 708for rotating and translating broach head 702. Broach control 706 mayinclude expansion control hub 710. Expansion control hub 710 may bedisplaceable along control shaft to expand or contract broaching member704. Broach head 702 may include distal end 780. Expansion control hub710 is shown in the “contract” position.

FIG. 8 shows broach 700 deployed in bone B through hole H. Broach 700may be deployed while broaching member 704 is contracted.

Broach head 702 may be advanced, through intramedullary space IS, intometaphyseal region M of bone B. Broach head 702 may be disposed in anyportion of intramedullary space IS, such as in the end-bone.

Access hole H may be sufficiently small that it reduces the occurrenceof cause stress risers at site H′. Expansion control hub 710 is shown inthe “expand” position and broaching member 704 is shown expanded in boneB. Broaching member 704 may be expanded during or after deployment.

A standard orthopaedic drill instrument (not shown) may be used to openaccess hole H in cortical bone BCO (shown in FIG. 2) at site H′ on boneB. The drill instrument may be guided by apparatus such as guide 100(shown in FIG. 1). Axis hole H may be drilled along broach axis LC.Broach axis LC may form an angle β with bone axis LB. Broach 700 may bepositioned such that broach axis Lc substantially coincides with guidetube axis LGT (shown in FIG. 1). Angle β may be an acute angle. Angle βmay be complementary with angle α (shown in FIG. 1).

FIG. 9 shows illustrative instrument guide 900 at site H′ on bone B.Instrument guide 900 may have one or more features in common withinstrument guide 100 (shown in FIG. 1). Instrument guide 900 may includeinstrument templates 930 and 932 for positioning instrument guide 900such that an instrument can be positioned at target region St1.

Illustrative steerable broach 950 may be deployed at target region St1in intramedullary space IS by insertion through guide 900 at site H′.Broach 950 may include broach head 925. Broach head 925 may have one ormore features or properties in common with broach head 125 (shown inFIG. 1). Broach head 925 may be supported by broach sheath 927. Broachhead 925 may be rotated by drive shaft 940 which may extend insidebroach sheath 927 and receive torque from torque adapter 908. Torqueadapter 908 may provide rotation from any suitable rotation source driveshaft 940.

Broach sheath 927 may be flexible. Broach sheath 927 may be flexible inregion 928 such that application of off-axis tension by elevator ribbon952 may position broach head 925 at a distance y or −y relative to boneaxis L_(B). Illustrative elevator control body 960 may apply axialcompression to elevator ribbon 952 to cause broach sheath 927 to bend.

Broach sheath 927 may be configured to flex in more than one plane.Broach sheath 927 may be configured to flex substantially in one planeonly.

Target region S_(t1) could be in either, or both, of cancellous boneB_(CA) and cortical bone B_(CO) (shown in FIG. 2). Side template 930 andtop template 932 are registered to guide tube 920. A practitioner mayposition templates 930 and 932 such that templates 930 and 932 “project”onto target region S_(t1) so that guide 900 will guide broach head 925to target region S_(t1).

Side template 930 may be rotatable at arm 942 to change angle γ betweenside template 930 axis L_(T) and guide 900 centerline CL_(GT). γ may beselected to correspond to a degree of elevation in direction y or −y ofbroach head 925. γ may be selected to correspond to a degree ofactuation of control 962 of control body 960. For example, γ may beselected such that side template 930 “projects” onto target region St2.

Fluoroscopic imaging may be used to position templates 930 and 932relative to target region St1.

A practitioner can select the position of H′ (distance x_(H) shown inFIG. 2), the angle of hole H (shown in FIG. 2) relative to bone axis LB,the degree and distribution of flexing in region 928, the penetration ofbroach sheath 927, the size of broach head 925, the swept-out profile ofbroaching member 924, and any other suitable parameters, to determinethe size, shape, orientation and location of a cavity to be swept out bybroaching member 924. For example, one or more of the aforementionedparameters may be selected to position broach head 925 in target regionSt2.

FIG. 10 shows guide base 102 from below on the distal side. Stem 116extends from the top of base 102. Guide tube 120 extends from the distalportion of base 102. Arm 131 extends from the side of base 102. Site H′of hole H (shown in FIG. 2) is shown projected onto opening 1002 ofguide tube 120 and centered about axes LH and LGT.

Illustrative contacts 108 and 110 extend down from base 102 to engagebone B (shown in FIG. 2) and resist rotation about vertical axes L_(H)and L_(TR) and translation along guide centerline CL_(G). Contacts 108and 110 may be sufficiently sharp to penetrate or partially penetratebone B. Cleats 112 and 114 may engage the surface of bone B and resistrotation about guide centerline CL_(G). Base 102 may support anysuitable number of contacts in any suitable pattern or location. Base102 may support an arrangement of contacts that extends in a directionthat is substantially oblique or transverse to guide centerline CL_(G).

In some embodiments, base 102 may include a flange (not shown) thatsaddles bone B. The flange may include any suitable number of contactsin any suitable pattern, including an arrangement of contacts thatextends in a direction that is substantially oblique or transverse toguide centerline CLG.

Alignment members 104 and 106 may extend from base 102 to align guidecenterline CLG of guide 100 with bone centerline CLBS of the top surfaceof bone B (shown in FIG. 2). Each of alignment members 104 and 106include continuous alignment edges 1004 and 1006. Edge 1004 is supportedby substantially vertical struts 1007 and 1008. Edge 1006 is supportedby substantially vertical struts 1010 and 1012. Edges 1004 and 1006 aresubstantially parallel to centerline CLG.

In some embodiments, alignment members may be or may include tines thatcorrespond to struts 1007, 1008, 1010 and 1012. One or more of the tinesmay extend straight down from base 102. One or more of the tines mayextend down and in the proximal direction relative to base 102. One ormore of the tines may extend down and in the distal direction relativeto base 102.

In embodiments that include one or more tines (not shown), edges 1004and 1006 may be absent. In those embodiments, the tines may flexindependently of each other. One or more of the tines may be biased awayfrom guide centerline CLG. One or more of the tines may be biased towardguide centerline CLG. One or more of the tines may be curved or arcuate.

Some embodiments may include a bushing (not shown) in guide tube 120.The bushing may provide stability for a K-wire in procedures in whichthe K-wire is used as a drill to provide preliminary access to theinside of a bone.

FIG. 11 shows illustrative saw 1100. Saw 1100 may be used to cut anaccess hole at site H′ or site I′ (shown in FIG. 2) or any othersuitable hole. Saw 1100 may be guided by guide 100 (shown in FIG. 1),guide 900 (shown in FIG. 9), guide 1900 (shown in FIG. 19) or any othersuitable guide.

Saw 1100 may include wire 1102. Wire 1102 may be a K-wire or any othersuitable wire. Saw 1100 may include centering sleeve 1104. Centeringsleeve 1104 may be made of polymer, alloy or any other suitablematerial. Saw 1100 may include cutting member 1106. Cutting member 1106may include teeth 1108, vents 1110 and cylindrical member 1112. Vents1110 may provide chip clearance, side-cutting, reduced heating or otherproperties, among others. Saw 1100 may include torque adapter 1114.Torque adapter 1114 may transmit rotation from a rotation source to oneor both of K-wire 1102 and cutting member 1106.

Wire 1102 may form an angled pilot hole in bone B. The hole may beformed at angle δ between saw axis L_(s) and bone axis L_(B). After wire1102 penetrates bone B, saw 1100 may be advanced distally until teeth1108 engage bone B and being to cut. Teeth 1108 will engage bone B firstat point p, in the crotch between wire 1102 and bone B. Teeth 1108 maytherefore be subjected to a contact force from bone B that is oblique toa plane defined by teeth 1108. Centering sleeve 1104 may support teeth1108 against the oblique force and maintain teeth 1108 at asubstantially constant radius from axis L_(s) during the formation of anaccess hole.

A spring 1116 (shown in FIG. 13) may urge centering sleeve 1104 distallyto keep centering sleeve 1104 at or near bone B as teeth 1108 penetrateinto bone B.

FIG. 12 shows that centering sleeve 1104 may be coaxially arrangedwithin cutting member 1106. Wire 1102 may be coaxially arranged withincentering sleeve 1104. Collar 1202 of centering sleeve 1104 may beprovided at a distal end of centering sleeve 1104 to provide a closetolerance between wire 1102 and centering sleeve 1104.

FIG. 13 shows spring 1116 compressed between proximal face 1302 ofcentering sleeve 1104 and distal face 1304 of torque adapter 1114.

In some embodiments, wire 1102 may be used to drill a pilot hole in boneB without apparatus such as centering sleeve 1104 and cutting member1106. In such embodiments, a bushing (not shown) may be provided in aguide tube such as guide tube 120 (shown in FIG. 1). Wire 1102 may beplaced through the bushing and driven by a torque adapter such as 1114.The bushing may have a bore that is sized to stabilize a K-wire drivenin rotation by a surgical drill.

It may be desirable thereafter to cut in the bone a hole that issubstantially coaxial with the K-wire. After the K-wire is drilled intothe bone, in such embodiments, the bushing (not shown) may be removedfrom the guide tube to allow a coring saw to advance through the guidetube.

FIG. 14 shows illustrative apparatus 1400 for cutting in bone B a holethat is substantially coaxial with wire 1402. FIG. 14 shows a relevantportion of coring saw guide 1450. Coring saw guide 1450 may includecontacts 1452 for engaging a surface of bone B (shown in FIG. 2). Coringsaw guide 1450 may include handle-mounting recesses such as 1454. Acentering sleeve (not shown) may be disposed coaxially between wire 1402and cutting member 1406. In some embodiments, a cutting member such as1406 may be engaged by a collar (not shown) that is configured fordelivery of torque.

A proximal end of wire 1402 may be engaged in a hand drill fitting androtatingly driven into the bone as it is advanced distally through sawguide 1450.

FIG. 15 shows wire 1402. Distal end 1502 of wire 1402 may have a firstdiameter. Proximal end 1504 of wire 1402 may have a second diameter thatis greater than the first diameter. Step 1506 between the first diameterand the second diameter may be used as a stop to limit the extent towhich wire 1402 may be driven into bone B.

Proximal end 1504 of a wire such as 1402 may extend along and through acannula in an A-O type adapter while the adapter drives a cutting membersuch as 1408 distally into a bone.

In some embodiments, step 1506 may be used to distally eject a bone plugfrom the interior of distal end 1405 of cutting member 1406 after a holeis cut and cutting member 1406 is withdrawn from the bone.

In some embodiments, a soft-tissue protector (not shown) may be providedto keep soft tissue proximate the access hole from becoming engaged byrotating apparatus. The protector may include a cannula for guiding therotating apparatus into the hole. The protector may include a flangethat “funnels” the apparatus into the cannula and blocks the soft tissuefrom approaching the apparatus.

FIG. 16 shows a portion of illustrative cutting member 1106 from region16 of FIG. 11. A circumferential tooth 1602 may extend into one or moreof vents 1110 to engage bone on the inside of the cutter.

Tooth 1602 may provide friction between cutting member 1106 and the boneplug and may facilitate removal of the bone plug upon with drawal ofcutting member 1106 from the access hole. The distal end of the boneplug may not be severed from bone B native tissue by cutting member1106. Tooth 1602 may provide one or both of torsional and axial force tosever the plug from bone B. Vents 1110 may include vent edges 1604. Ventedges 1604 may cut a wall of the access hole.

Tooth 1602 may provide friction between cutting member 1106 andcentering sleeve 1104. The friction may resist proximal motion ofcentering sleeve 1104.

FIG. 17 shows illustrative teeth 1108 of cutter member 1106 (shown inFIG. 11). Illustrative tooth 1702 may include cutting edge 1704, face1706 and back 1708. Face 1706 and back 1708 may partially defineadjacent gullets 1710 and 1712, which intervene between tooth 1702 andneighboring teeth 1714 and 1716, respectively. Tooth 1702 may havethickness t. Tooth 1702 may be circumferentially set apart fromneighboring tooth 1716 by pitch P_(t). Cutting edge 1704 may be angledrelative to saw radial direction R_(s) by bevel angle φ (shown on adifferent tooth). Cutting edge 1704 is shown with φ=0°, but any suitableφ may be used. Face 1706 may have longitudinal rake angle ρ.

Larger rake angles (e.g., positive) may produce lower forces, butsmaller included tooth angles, and therefore lower heat capacity.Smaller rake angles (e.g., negative) may increase heat capacity andincrease heat generated in shearing but increase cutting forces.

Face 1706 is shown with ρ=0°, but any suitable ρ may be used. Gullet1710 may have gullet depth D_(g).

In some embodiments, tooth 1702 may include facet 1718 (shown in brokenline). When facet 1718 is present, tooth face 1706 may be shortened bydistance h. Facet 1718 may have a normal (not shown) that is oriented atany suitable angle relative to axis L_(s) and radius R_(s).

FIG. 18 shows teeth 1108 (shown in FIG. 11) as viewed along lines 18-18(shown in FIG. 17). Cutting edge 1704 forms angle θ with saw outer wall1802. Cutting edge 1704 is shown with θ≈90°, but any suitable θ may beused. For example, a tooth formed by cutting along chord Ch₁ may createa cutting edge having θ>90°. A tooth formed by cutting along chord Chemay create a cutting edge having θ<90°.

In some embodiments, a cutting member may have bi-directionally cuttingteeth. Each tooth such tooth may have a right and a left cutting edge.When the coring saw rotates clockwise, a right edge cuts. When thecoring saw rotates counterclockwise, a left edge cuts.

FIG. 19 shows illustrative instrument guide 1900. Illustrativeinstrument guide 1900 may have one or more features in common with oneor more of guide 100 (shown in FIG. 1) and guide 900 (shown in FIG. 9).Guide 1900 may be used to guide an instrument into bone B at a site suchas H′ or I′ (shown in FIG. 2).

Guide 1900 may include base 1902. Base 1902 may be placed against bone B(shown in FIG. 2) at site H′. Base 1902 may include contacts (notshown), alignment members (not shown), cleats (not shown) or any othersuitable features. Grip 1918 may extend from base 1902. Base 1902 mayinclude pivot 1904. Pivot 1904 may pivotably support guide tube 1920.Guide tube 1920 centerline CL_(GT′) may be positioned at any suitableangle α′ relative to axis L_(H)′ so that saw 1950 may be advancedthrough bone B (not shown) at angle α′. The intersection of axis L_(H′)and CL_(GT′) may substantially coincide with site H′ or site I′ fordifferent values of α′. A practitioner may change angle α′ before orduring penetration of saw 1950 into bone B. For example, a practitionermay initiate a pilot hole at α′≈0° and then change α′ to obtain thedesired angle for the access hole.

Saw 1950 may include teeth 1952, flutes 1954, cannula 1956 or any othersuitable features, including the features described and shown herein inconnection with other saws.

FIG. 20 shows a view of a distal portion of broach 700 taken along lines20-20 (shown in FIG. 7). Pin 703 may be located near the distal end ofbracket 720. Pin 703 may fix the position of the distal end of broachingmember 704. Pin 703 may support cylindrical form 705. Cylindrical form705 may be coaxially mounted on pin 703. Cylindrical form 705 maysupport a spiral segment of broaching member 704. One or more distalportions of broaching member 704 may be welded or otherwise suitablyfixed to cylindrical form 705.

Cylindrical form 705 may constrain or partially constrain theorientation of distal portions of broaching member 704. Cylindrical form705 may be fixed relative to bracket 720. Cylindrical form 705 may berotatable relative to bracket 720.

Broach head 702 may include end cap 701. Broaching member 704 may removetissue that is generally proximal end cap 701. In some embodiments,member 704 may expand in such a manner as to extend distally of end cap701. In such embodiments, the broaching member may remove tissue that isdistal of end cap 701.

Reducing or minimizing the distance between the distal end of broachingmember 704 and end cap 701 may allow broaching member 704 to removetissue that is more immediately proximal end cap 701. End cap 701 may bepositioned at the distal end of bracket 720. End cap 701 may beconfigured to have a smooth, atraumatic surface. Bracket 720 may beattached to drive shaft 730.

Shaft assembly 714 may include drive shaft 730. Drive shaft 730 maysupport bracket 720 at union 732. Drive shaft 730 may be secured tobracket 720 by pin 734. Drive shaft 730 may provide rotation to broachhead 702.

Proximal ends 736 and 738 of broaching member 704 may be fixed to slide740, which may be a tube. Proximal end 738 may be threaded through orkeyed into windows 742 and 744 in slide 740. Proximal end 736 may bethreaded through or keyed into slots 746 and 748 in slide 740. Slide 740may slide relative to drive shaft 730 to expand and contract broachingmember 704. Slide 740 is shown in the “contract” state, in whichbroaching member 704 is drawn close to bracket 720. Slide cover 750 mayslide with slide 740. One or both of slide 740 and slide cover 750 maybe translated along axis L_(c) by control hub 710 (shown in FIG. 7) orany other suitable position controller.

Slide cover 750 may remain stationary relative to drive shaft 730 whenslide 740 slides relative to drive shaft 730. In embodiments in whichslide cover 750 remains stationary when slide 740 moves, distal end 752of slide cover 750 may limit the radial position of broaching member 704at a fixed distance along drive shaft 730 and thus affect thedeformation of broaching member 704 in the expanded state.

Broaching member 704 may undergo one or both of elastic and plasticdeformation.

FIG. 21 shows a view of a distal portion of broach 700 taken along lines20-20 (shown in FIG. 7) when broaching member 704 is in an expandedstate. Broaching member 704 is shown as mainly circular. However, anydesired shape may be able to be imparted in the expanded state such asbut not limited to: square, triangular, oval, ellipsoid, teardrop,football, or any other suitable shape.

Different shapes may be obtained using several methods, such asutilizing a pre-set shape in a shape memory alloy, modifying thegeometry of the member cross-section (along the member length) such thatit preferentially bends in a desired manner, constraining broachingmember 704 (e.g., in force, shear or moment) in a way that forces theexpansion to take desired shape, having the final shape be that of theexpanded geometry and the reduced or collapsed geometry be that of ahigher strain configuration, and/or any other suitable method of forminga desired shape.

For example, largely or substantially preventing radial movement ofbroaching member proximal ends 736 and 738, and allowing movement of thedistal end of broaching member 704 generally about pin 703 whileelastically deforming broaching member proximal ends 736 and 738, due toreducing the distance between the distal end and proximal ends 736 and738 of broaching member 704, may modify the geometry of broaching member704 from a generally straight configuration to a generally eggbeatershape.

The deformation may relatively increase the distance between (a)sections 760 and 762 and (b) bracket 720. As this distance is increased,the swept-out volume of broaching member 704, as broaching member 704rotates generally about an axis such as Lc (shown in FIG. 8), isincreased.

In some embodiments, a broach may include a broaching member thatincludes one or more stiff tines (not shown) that is joined to a driveshaft. The drive shaft may have a longitudinal axis. The tine may bejoined to the drive shaft radially close to the axis at a proximal endof the tine. The tine may have a distal end that is spaced radiallyapart from the axis. The distal end of the tine may be distal of thedistal end of the drive shaft. There may be numerous tines on the driveshaft. Such embodiments may be appropriate for rotation inintramedullary space IS of bone B (shown in FIG. 2) using high torque atlow rotational speeds.

FIG. 22 shows broaching member 704 in partial cross section from viewlines 22-22 (shown in FIG. 21). Broaching member 704 may have leadingedges 2202 and 2204 that may be rotated in direction ω_(c) by driveshaft 730 (shown in FIG. 21). Broaching member 704 may sweep out a spacein bone B (shown in FIG. 2) based on radius R_(c), which corresponds tosections 760 and 762 (shown in FIG. 21).

Leading edge 2202 may be beveled at angle α_(c1). Angle α_(c1) may beany suitable angle, including an angle from about 5° to about 75°. Angleα_(c1) may cause leading edge 2202 to be generally sharp or knife-like.This may aid in the broaching member's ability to remove tissue.

Leading edge 2204 may be beveled at angle α_(c2). Angle α_(c2) may beany suitable angle, including an angle from about 5° to about 75°. Angleα_(c2) may cause leading edge 2204 to be generally sharp or knife-like.This may aid in the broaching member's ability to remove tissue.

As broaching member 704 is rotated clockwise generally about axis L_(c)leading edges 2202 and 2204 may generally be the first portion ofsections 760 and 762 to come in contact with tissues such as relativelyless dense cancellous bone B_(CA) (shown in FIG. 2). Sections 760 and762 may be configured to be sufficiently flexible such that if either ofsections 760 and 762 contacts relatively more dense materials, such asdiaphysis, metaphysis and epiphysis bone, sections 760 and 762 maydeflect generally radially in direction −ω_(o) about axis L_(c) and/orin the linear direction towards axis L_(c) at any location along thelength of sections 760 and 762 or any other portion of broaching member704. Deflection or deformation of sections 760 and 762 may have theaffect of not disturbing the more dense tissues.

Leading edges 2202 and 2204 may be offset from axis L_(c) by offsets Δ₁and Δ₂ respectively. Appropriate magnitudes of offsets Δ₁ and Δ₂ may beselected. In some embodiments, offsets Δ₁ and Δ₂ may be constrained bythe collapsed diameter (overall diameter of broach head 702 in a planetransverse to axis L_(c) when broaching member 704 is collapsed, e.g.,for deployment) of the configuration and the desired expanded engagement(radius R_(c)) of broaching member 704 with the tissue. Offsets Δ₁ andΔ₂ may aid in the broaching member's efficiency at displacing tissue.

FIG. 22A shows broach head 704 in intramedullary space IS of bone B andillustrates how flexible broaching members can broach bone of arelatively lower density and be deflected by bone of a relatively higherdensity. Sections 760 and 762 have displaced or removed some ofcancellous bone B_(CA) from bone B by rotating in direction ω_(c) aboutaxis L_(c). Sections 760 and 762 may be sufficiently stiff to removecancellous bone to radius R_(c) from axis Lc in the “top” portion ofbone B. Because of the placement of axis L_(c) relative to the bottomportion of bone B, sections 760 and 762 contact cortical bone BCO at thebottom of bone B. Sections 760 and 762 may be sufficiently flexible tobe deflected by cortical bone BCO. Section 760 is shown deflected indirection −ω_(c) by bone BCO. Sections 760 and 762 thus remove bone onlyto radius R_(c)′ in the “bottom” portion of bone B.

The cavity created by broach 700 may thus be bounded in part bycancellous bone BCA and in part by cortical bone BCO. The shape of thecavity portion that is bounded by cancellous bone BCA may be governedsubstantially by the geometry and mechanical properties of broach 700.The shape of the cavity portion that is bounded by cortical bone BCO maybe governed substantially by the native anatomy of bone B.

FIG. 23 shows a view of broach 700 along lines 23-23 (shown in FIG. 20).Broach 700 is in the contracted state. Slide cover 750 has been removed.Slots 746, 748 and 2302 in slide 740 may be configured to coincide withfeatures on proximal end 736 (shown in FIG. 21) of broaching member 704.When proximal end 736 is engaged with slots 746, 748 and 2302, slots746, 748 and 2302 may restrict movement of proximal end 736 in eitherdirection generally along axis L_(c). Slots 746, 748 and 2302 may haveany suitable geometry that allows for the engagement and axialtranslation of proximal end 736.

Slots 746, 748 and 2302 may be of sufficient depth that, when proximalend 736 is engaged in slots 746, 748 and 2302, slide cover 750 (shown inFIG. 20) has adequate radial clearance with respect to proximal end 736and slide 740 to slide over slide 740 and slots 746, 748 and 2302. Aninner surface of slide cover 750 may prevent movement of proximal end736 from moving in a direction generally away from axis L_(c).

Slide 740 may include slots (not shown) that correspond to proximal end738 (shown in FIG. 20) and have one or more features in common with,slots 746, 748 and 2302.

Broach head 720 may include broaching member wrap section 2304. Pin 703may be integrated into wrap section 2304. Wrap section 2304 may beseparate from pin 703. Wrap section 2304 may be configured to allowwrapping of broaching member 704 generally around wrap section 2304.Broaching member 704 may be looped in wrap section 2304. Broachingmember 704 may be wrapped (as shown in FIG. 23) at least one full turnin wrap section 2304. Wrapping about wrap section 2304 may bias segments760 and 762 (shown in FIG. 21) away from axis L_(c).

FIG. 24 shows a cross section, viewed along lines 24-24 (shown in FIG.8) of a portion of broach control 706 (shown in FIG. 7). Expansioncontrol hub 710 is shown with base 2402 at position p_(e). This maycorrespond to the expanded state of broaching member 704, as shown inFIG. 8. Base 2402 may be moved distally to position p_(c). This maycorrespond to the contracted state of broaching member 704, as shown inFIG. 7. Expansion control hub 710 may operate in connection with body2408. Body 2408 may include control shaft 712 and distal stop 2410.Control shaft 712 may include threads 2418.

Expansion control hub 710 may include outer member 2412 and inner member2414. Outer member 2412 and inner member 2414 may be fixed to eachother. Slide pin 2404 may be captured between outer member 2412 andinner member 2414. Inner member 2414 may include threads 2416 forengagement with threads 2418 on control shaft 712. Slide pin 2404 maytravel in slots 2405 and 2407 in body 2408.

Expansion control hub 710 may be moved along axis L_(c) by applyingforce to expansion control hub 710. In some embodiments, expansioncontrol hub 710 may be advanced axial generally along axis L_(c) byapplying rotational force generally about axis L_(c) to expansioncontrol hub 710 such that threads 2416 move advance or retreat throughthreads 2418.

Axial movement of expansion control hub 710 relative to body 2408 may betransferred to slide 740 and slide cover 750 while drive shaft 730remains axially fixed to body 2408 by pin 2406. Slide 740 may includecut-outs 2430 and 2432. Slide cover 750 may include cut-outs 2434 and2436. Cut-outs 2430, 2432, 2434 and 2436 may provide clearance of pin2406 when slide 740 and slide cover 750 travel axially.

When expansion control hub 710 is moved axially, proximal ends 736 and738 (shown in FIG. 20) of broaching member 704 thus move axially. Distalend 780 (shown in FIG. 7) of broaching member 704 may be axially fixedto drive shaft 730, which may be fixed to body 2408. Thus, whenexpansion control hub 710 moves distally, the distance between (a)proximal ends 736 and 738 and; (b) distal end 780 decreases andbroaching member 704 expands. When expansion control hub 710 movesproximally, the distance between (a) proximal ends 736 and 738; and (b)distal end 780 increases and broaching member 704 contracts.

Distal stop 2410 and proximal stop 2420 may limit axial movement ofexpansion control hub 710. Although proximal stop 2420 is shown as beingpart of handle 708, proximal stop 2420 may be separate from handle 708.

Handle 708 may transfer rotational motion generally about axis L_(c) tocontrol shaft 712. Control shaft 712 may transfer the rotation to slidepin 2404 and drive shaft pin 2406. Slide pin 2404 may transfer therotation to slide 740 and slide cover 750. Drive shaft pin 2406 maytransfer the rotation to drive shaft 730, which may drive broachingmember 704 (shown in FIG. 21).

Distal stop 2410 is shown as being integral with body 2408, but distalstop may be a separate element that is attached to control shaft 712 ora different part of body 2408.

Pin 2406 may extend into recess feature 2422. Recess feature 2422 may bea through-hole. Pin 2406 may extend through the through hole to alocation external to body 2408.

Pin 2404 may extend into recess feature 2424. Recess feature 2424 may bea through-hole. Pin 2404 may extend through the through-hole to alocation external to body outer member 2412. Recess feature may extendcircumferentially about axis L_(c). If recess feature 2424 extendscircumferentially about axis L_(c), expansion control hub 710 may rotateabout axis L_(c) substantially without restricting, or being restrictedby, pin 2404.

Body 2408 may include circumferential recess 2426. Recess 2426 may besized to engage O-ring 2428. Recess 2426 may prevent axial movementbetween body 2408 and O-ring 2428 generally along axis L_(c). O-ring2428 may be sized to provide an interference fit with outer member 2412.The interference fit may produce friction between O-ring 2428 andexpansion control hub 710. The friction may allow expansion control hub710 to be lightly locked at any rotational position relative to body2408, generally about axis L_(c).

FIG. 25 shows illustrative cavity preparation apparatus 2500. Apparatus2500 may include broach 2550. Broach 2550 may have one or more featuresin common with broach 950 (shown in FIG. 9). Broach 2550 may include oneor more of broach head 2525, elevator ribbon 2552 and control body 2560.Apparatus 2500 may include guide 2502. Guide 2502 may guide broach 2550or any other suitable apparatus through an access hole such as H or I(shown in FIG. 2). Guide 2502 may retain soft tissue at a distance fromthe access hole to prevent engagement of the soft tissue by aninstrument that is present in guide 2502.

FIGS. 26-29 show features of different portions of apparatus 2500.

FIG. 26 shows in partial cross section illustrative broach head 2525 andillustrative elevator ribbon 2552.

Broach head 2525 may be driven about axis L_(E) by rotating drive shaft2540. Broach head 2525 may include broaching member 2524, which may haveone or more features in common with broaching member 704 (shown in FIG.7). Broach head 2525 may include distal hub 2526 and proximal hub 2528.One or both of distal hub 2526 and proximal hub 2528 may transferrotation to broaching member 2524. One or both of distal hub 2526 andproximal hub 2528 may support broaching member 2524.

Drive shaft 2540 may extend within broach sheath 2527. Drive shaft 2540may be supported in rotation by bushing 2530 at the end of broach sheath2527.

Illustrative elevator ribbon 2552 may be anchored to broach sheath 2527at fixation 2532. When axial compressive force, generally along axisL_(E), is applied to elevator ribbon 2552, elevator ribbon 2552 maybuckle along its length. For example, elevator ribbon 2552 may buckle ator near section 2534. Section 2536 may be used to support broach sheath2527 at an elevation relative to cancellous bone B_(CA) or cortical boneB_(CO) in bone B (shown in FIG. 2).

Portions of elevator ribbon 2552 may extend inside broach sheath 2527and pass through slots 2542 and 2544 to section 2534. In someembodiments, there may be contact between drive shaft 2540 and elevatorribbon 2552. In some embodiments, there may be no contact between driveshaft 2540 and elevator ribbon 2552.

Elevator ribbon 2552, when compressed, may apply tension to adjacentportion 2538 of broach sheath 2527 and compression to opposite portion2540 of broach sheath 2527. One or both of the tension of adjacentportion 2538 and the compression of opposite portion 2540 may causebroach sheath 2527 to curve generally about an axis such as L_(F).

One or both of adjacent portion 2538 and opposite portion 2540 mayinclude stress-relief features that allow bending under tension andcompression. The stress-relief features may include slots or slotpatterns. The stress-relief features may be provided usinglaser-cutting. The stress-relief may provide an equilibrium curvaturesuch that broach sheath 2527 is curved at rest.

The stress-relief features may include sintered particles. The particlesmay include metal, polymer, composite or any other suitable material.

FIG. 27 shows illustrative laser-cut pattern 2700 for a broach sheathsuch as 927 (shown in FIG. 9) or 2527 (shown in FIG. 26). Pattern 2700,which is shown flat for illustration, may be cut in a cylindrical tubeto relieve compression on one side of the tube and relieve tension onthe other side of the tube. For example, compression relief pattern 2740may be provided along opposite portion 2540 of broach sheath 2527.Tension relief pattern 2738 may be provided along adjacent portion 2538of broach sheath 2527. Tension and compression relief may be increasedby lengthening lengths L_(p1) and L_(p2), respectively. Bendingstiffness may be reduced by increasing pattern widths w₁ and w₂.Increasing kerf and decreasing inter-cut spacing may also decreasebending stiffness. In some embodiments, the tube may have an outerdiameter of 0.108 in. In some embodiments, the tube may have an outerdiameter of 0.125 in. Any suitable outer diameter may be used.

FIG. 28 shows illustrative elevator control body 2860. Elevator controlbody 2860 may support the proximal end of broach sheath 2527. Driveshaft 2540 may extend through control body 2860 to torque adapter 2808.Torque adapter 2808 may be cannulated. Torque adapter 2808 may be acannulated A-O type adapter. Torque adapter 2808 may have a “D”-shapedextension for engagement by a D-shaped chuck.

Torque adapter 2808 may be torqued by any suitable source of rotationalenergy.

Control body 2860 may include housing 2862 and actuator 2866. Handle2864 may be used to rotate actuator 2866 through angle δhd E about axisL_(TE) relative to housing 2862. When actuator moves through angleδ_(E), shaft 2868 may drive shuttle 2870 in slot 2872. The distal end ofelevator ribbon 2552 may be fixed to the shuttle, for example, by screw2874. When the shuttle is in a distal position, elevator ribbon 2552 isexpanded (as shown in FIG. 26). When the shuttle is in a proximalposition, elevator ribbon 2552 is contracted toward axis L_(E).

Actuator 2866 may include face member 2890. Face member 2890 may befixed relative to housing 2862. Face member 2890 may include recess2892. Recess 2892 may “catch” a projection such as 2894 to act as adetent. Projection 2894 may be one of several projections that providedetent positions. For example, three detent positions may be provided:forward, neutral and back. In the forward position, elevator ribbon 2552is extended. In the back position, elevator ribbon 2552 is compressed.In the neutral position, elevator ribbon 2552 is in a partiallycompressed state.

Housing 2862 may be configured to house a torque limiter (not shown).The torque limiter may couple torque adapter 2808 to drive shaft 2540and may be used to limit the torque that is applied to broach head 2525(shown in FIG. 25). If broach head 2525 were to jam in bone B (shown inFIG. 2), the torque limiter may cap or reduce the torque on broachinghead 2525 to prevent damage to broaching head 2525, other elements ofapparatus 2500, other involved apparatus or bone B.

FIG. 29 shows illustrative guide 2502. Guide 2502 may include cannula2904 and funnel 2906. Funnel 2906 may facilitate insertion of a broachhead such as 2525 (shown in FIG. 25) into a hole such as H (shown inFIG. 2).

Guide 2502 may be “preloaded” on broach sheath 2527. A practitioner mayinsert a broach head into hole H (shown in FIG. 2) and then positionguide 2520 in hole H. Funnel 2906 may protect soft tissue outside boneB. Cannula 2904 may guide the broach head through hole H when broachhead is withdrawn from hole H (for example, at the conclusion of acavity preparation procedure).

Outer wall 2908 of cannula 2904 may be of an appropriate diameter tosubstantially fill hole H. Funnel 2906 may include ledge 2910. Ledge2910 may limit the extent to which cannula 2904 may extend intointramedullary space IS.

Cannula 2904 may support detent 2912. Detent 2912 may be present tocatch on the inside of cortical bone B_(CO) wall W to retain cannula2904 in position in hole H. Detent 2912 may be have a tapered profile sothat it can engage walls W of different thickness. In some embodiments,detent 2912 may be passive. In passive embodiments, detent 2912 may beresilient, biased or rigid. In some embodiments, detent 2912 may beactive. In active embodiments, detent 2912 may be actuated. For example,detent 2912 may be actuated by a manual control that causes detent 2912to extend away from tube cannula 2904 a desired distance or a presetdistance. Cannula 2904 may include more than one detent.

Mouth 2914 of funnel 2906 may have any suitable shape transverse to axisL_(E). The shape may be rectangular, triangular, elliptical, tear-drop,splayed, circular and any other suitable shape.

Funnel 2906 may include a skiving-curved section (not shown). Theskiving-curved section may be at the distal end of funnel 2906.

Guides for rotatable broaches may include a body that has a cannula. Thebody may support a broach sheath in alignment with the cannula. A driveshaft may pass through the cannula and extend distally through thebroach sheath. A rotation source may be connected to the drive shaftproximal the body. The body may be hand-held. The body may have noadaptations to mate with a hole such as H (shown in FIG. 2).

FIG. 30 shows apparatus 2500 (shown in FIG. 25) with control 2864 at alarger angle δ_(E) and elevator ribbon 2552 in the contracted stateclose to broach sheath 2527. Stress-relief features such as those shownin flat model 2700 (shown in FIG. 27) are shown in portions 2538 and2540 of broach sheath 2527.

FIG. 31 shows illustrative broaching member 3102. Broaching member 3102may be mounted by fixture 3104 to hub 3106 at the distal end of a broachshaft 3108. Broach shaft 3108 may have one or more features in commonwith broach shaft 2527 (shown in FIG. 26) or any other broach shaftdiscussed or shown herein. For example, broach shaft 3108 may includestress-relief features 3110 and 3112.

Hub 3106 may have one or more features in common with hub 2528 (shown inFIG. 26).

Broaching member 3102 may be a self expanding structure. Broachingmember 3102 may be constructed from laser-cut tube stock that isexpanded into a suitable shape, such as that shown. Broaching member3102 may include broaching members such as 3114. Broaching member 3102may include numerous interconnected cells such as cell 3116. The cellsmay be defined by one or more broaching members. Some cells may bedefined by structures other than broaching members. The cells may bearranged in a network. The cells may be linked such that when thestructure is stressed (e.g., compressed) at a point the stress isdistributed to nearby cells. Broaching member 3102 may thus rotate in abone cavity that has an irregular shape, for example, nonround, oblong,or angular. The cavity may be smaller than a diameter of broachingmember 3102, such as expanded diameter D_(E).

Broaching member 3102 may include broaching members that includedbraided wire (not shown). Broaching member 3102 may include broachingmembers that included braided ribbon (not shown).

In some embodiments, each cell arm may be a broaching member. When alarge number (i.e., when the circumferential density of broachingmembers is high) of broaching members are present during the rotation ofa broaching head, a relatively lower torque is required to drive thebroaching head.

FIG. 32 shows illustrative broach 3200 inserted in bone B. Broach 3200may include broaching head 3202. Flexible rotating drive shaft 3204 maydrive broaching head 3202 in rotation in directions ρ′ or −ρ′. Driveshaft 3204 may be driven by a rotation source such as handle 3206. Insome embodiments, the rotation source may include a surgical hand drill,a dremel motor or any other suitable rotational power source.

Drive shaft 3204 may be sheathed in a flexible cannula (apart frombroach sheath 3210, which is described below).

Control body 3208 may be used to insert broaching head 3202 through ahole at site H′. During insertion, broaching head 3202 may be withdrawninto flexible broach sheath 3210. Proximal end 3212 of flexible broachsheath 3210 may be fixed to distal end 3214 of control body 3208.Actuator 3216 may engage drive shaft 3204 and may slide relative tocontrol body 3208. Actuator 3216 may thus translate drive shaft 3204along axis L_(M) within guide sheath 3210.

In some embodiments, broaching head 3202 may be compressible andexpandable. Broaching head 3202 may be compressed within guide sheath3210. Broaching head 3202 may be expanded outside of guide sheath 3210.In some embodiments, broaching head 3202 may self-expand in bone B afterbeing pushed out of guide sheath 3210 by drive shaft 3204. In someembodiments, broaching head 3202 may be outside guide sheath 3210 whenbroaching head 3202 is delivered into bone B.

Broaching head 3202 may include one or more broaching members 3218 thathave sufficient rigidity to displace cancellous bone, but sufficientresilience to deform when brought into contact with cortical bone andthus leave the cortical bone substantially in place.

Broaching members 3218 may be formed from loops. The loops may be fixedto distal hub 3220. The loops may be fixed to proximal hub 3222. One orboth of distal hub 3220 and proximal hub 3222 maybe axially fixed todrive shaft 3204. One or both of distal hub 3220 and proximal hub 3222maybe rotationally fixed to drive shaft 3204. Broaching head 3202 mayinclude any suitable number of loops. Broaching members 3218 may haveone or more features in common with broaching member 704 (shown in FIG.7) or any other broaching member described or shown herein.

FIG. 33 shows illustrative broaching head 3300. Broaching head 3300 mayinclude broaching members 3302. Each of broaching members 3302 may haveone or more features in common with broaching member 704 (shown in FIG.7) or any other broaching member shown or described herein. Broachinghead 3300 may have any suitable number of broaching members 3302. Forexample, broaching head 3300 may have one broaching member, 2-6broaching members, 7-20 broaching members, more than 20 broachingmembers or any suitable number of broaching members.

Broaching head 3300 may be contracted toward drive shaft 3310 andwithdrawn into an outer sheath (not shown). The outer sheath may beinserted in a hole such as H (shown in FIG. 2). Broaching head 3300 maythen be deployed by retracting the sheath. Broaching members 3302 may besufficiently resilient to be contracted and may expand away from driveshaft 3310 when the sheath is retracted.

Broaching members 3302 may be supported by distal hub 3304. Distal hub3304 may be absent and broaching members 3302 may have free distal ends.Broaching members with free distal ends may be supported at theirproximal ends near the central axis of broaching head 3300. Thebroaching members may be angled radially away from the central axis ofbroaching head 3300.

Broaching members with free distal ends may have suitable shape at thedistal ends, such as pointed, forked, rounded, blunt or truncated.

Broaching members 3302 may be supported by proximal hub 3306. Proximalhub 3306 may be supported by broach sheath 3308. Broach sheath 3308 mayhave one or more features in common with broach sheath 127 (shown inFIG. 1).

Drive shaft 3310 may drive broaching head 3300 in rotation. Drive shaft3310 may extend distally to distal hub 3304. Drive shaft 3310 may extendthrough broach sheath 3308 to a proximal rotation source (not shown).

One or both of distal hub 3304 and proximal hub 3306 maybe axially fixedto drive shaft 3310. One or both of distal hub 3304 and proximal hub3306 maybe rotationally fixed to drive shaft 3310.

One or more of broaching members 3302 may include a hoop segment such as3312. Segment 3312 may support one or more reinforcements such as 3314.

Segment 3312 may be rigid. Segment 3312 may be resilient. Segment 3312may have any suitable pre-set curvature or be substantially linear.Segment 3312 may be a closed loop. The loop may be asymmetric.

Segment 3312 may include a length of wire, ribbon, cable, stranded wire,or any other suitable form or structure. Segment 3312 may includepolymer, metal, alloy or any other suitable material. Segment 3312 maybe constructed of a mesh cut from metal tube.

Reinforcement 3314 may be a tube. Reinforcement 3314 may be formed frompolymer, metal, alloy or any other suitable material. One or morereinforcements such as 3314 may be sized and positioned to supportsegment 3312 in a desired contour. One or more reinforcements such as3314 may provide bone-broaching abrasiveness, momentum or both.

FIG. 34 shows illustrative broaching head 3400. Broaching head 3400 mayinclude broaching members 3402. Each of broaching members 3402 may haveone or more features in common with broaching member 704 (shown in FIG.7) or any other broaching member shown or described herein. Broachinghead 3400 may have any suitable number of broaching members 3402. Forexample, broaching head 3400 may have one broaching member, 2-6broaching members, 7-20 broaching members, more than 20 broachingmembers or any suitable number of broaching members.

Broaching members 3402 may be supported by distal hub 3404. Broachingmembers 3402 may be supported by proximal hub 3406. Proximal hub 3406may be supported by drive shaft 3410. Drive shaft 3410 may have one ormore features in common with drive shaft 730 (shown in FIG. 20) or anyother drive shaft that is shown or described herein.

Drive shaft 3410 may drive broaching head 3400 in rotation. Drive shaft3410 may extend distally to distal hub 3404. Drive shaft 3410 may extendto a proximal rotation source (not shown).

One or both of distal hub 3404 and proximal hub 3406 maybe axially fixedto drive shaft 3410. One or both of distal hub 3404 and proximal hub3406 maybe rotationally fixed to drive shaft 3410.

One or more of broaching members 3402 may include a hoop segment such as3412. Reinforcement 3414 may support one or more segments such as 3412.

Segment 3412 may be rigid. Segment 3412 may be resilient. Segment 3412may include a length of wire, ribbon, cable, stranded wire or any othersuitable form or structure. Segment 3412 may include polymer, metal,alloy or any other suitable material.

Reinforcement 3414 may be a brace. Reinforcement 3414 may be formed frompolymer, metal, alloy or any other suitable material. One or morereinforcements such as 3414 may be sized and positioned to supportsegment 3412 in a desired contour. One or more reinforcements such as3414 may provide bone-broaching abrasiveness, momentum or both.

The brace may reduce material fatigue in segment 3412. The brace mayhelp segment 3412 retain its shape under forces of rotation andbroaching resistance. The brace may include loops such as 3418 and 3416.The loops may pass around the circumference of segment 3412. In someembodiments, loops 3418 and 3416 may encompass only a portion of thecircumference. In some embodiments, the brace may be fixed to segment3412, for example, by crimping, welding or press-fit.

The brace may support broaching edges for displacing bone material inbone B (shown in FIG. 2). The broaching edges may have any suitableform, such as serrated, saw-tooth, knife-edge, rectilinear edge or anyother suitable form.

The brace may be formed from a pattern that is cut into a metal tube.

FIG. 35 shows illustrative broaching head 3500. Broaching head 3500 mayinclude broaching member 3502. Broaching member 3502 may have one ormore features in common with broaching member 704 (shown in FIG. 7) orany other broaching member shown or described herein.

Broaching head 3500 may have any suitable number of broaching memberssuch as broaching member 3502. For example, broaching head 3400 may haveone broaching member, 2-6 broaching members, 7-20 broaching members,more than 20 broaching members or any suitable number of broachingmembers. When more than one broaching member is included, the broachingmembers may have different sizes or other features.

Broaching member 3502 is illustrated as a single solid hoop. Broachingmember 3502 may include one or more members that are stranded orbraided. Broaching member 3502 may include wire, strip stock, sheetstock, strand, ribbon, polymer, composite, ceramic, sintered material orany other suitable material. Broaching member 3502 may have one or moreof a variety of cross sections, such as square, rectangular, octagonal,contours with sharp edges, stranded cable, or other suitableconfigurations to facilitate bone displacement.

Broaching member 3502 may include stainless steel, Nitinol (shapeset,superelastic or other Nitinol) or any other suitable substance.

Broaching member 3502 may be a substantially continuous structure.Broaching member 3502 may pass through channel 3512 in distal hub 3504.Broaching member 3502 may be fastened to distal hub 3504 in channel3512.

Broaching member 3502 may be supported by distal hub 3504. Broachingmember 3502 may be supported by proximal hub 3506. Proximal hub 3506 maybe supported by broach sheath 3508. Broach sheath 3508 may have one ormore features in common with broach sheath 127 (shown in FIG. 1) or anyother broach sheath that is shown or described herein.

Drive shaft 3510 may drive broaching head 3500 in rotation. Drive shaft3510 may extend distally to distal hub 3504. Drive shaft 3510 may extendto a proximal rotation source (not shown).

One or both of distal hub 3504 and proximal hub 3506 maybe axially fixedto drive shaft 3510. One or both of distal hub 3504 and proximal hub3506 maybe rotationally fixed to drive shaft 3510.

Distal hub 3504 may be constructed of metal, stainless steel, laser-cuttube, polymer, ceramic or any other suitable material.

The distal end of drive shaft 3510 may extend into a channel (not shown)in distal hub 3504. Distal hub 3504 may be free to move axially withrespect to drive shaft 3510. The channel in distal hub 3504 may be keyedfor receiving a complementarily keyed distal end of drive shaft 3510.Drive shaft 3510 may thus drive broaching member 3502 distal portions3518 and 3520.

During rotation, broaching member 3502 may elongate axially, along axisL_(G) and push distal hub 3504 distally relative to drive shaft 3510.Such motion may contract broaching member 3502. During rotation,broaching member 3502 may expand axially along axis L_(G) and drawdistal hub 3504 proximally relative to drive shaft 3510. Contraction mayoccur, for example, when distal hub 3504 encounters resistant material.

Distal hub 3504 may be fixed to drive shaft 3510. Broaching member 3502may be driven rotationally by application of torque to proximal ends3514 and 3516 of broaching member 3502. Broaching member 3502 may bedriven rotationally by application of torque to distal portions 3518 and3520 of broaching member 3502.

Proximal ends 3514 and 3516 of broaching member 3502 may be affixed todrive shaft 3510 by proximal hub 3506. Proximal hub 3506 may engageproximal ends 3514 and 3516 by crimping, welding, set-screw, snap fit orany other suitable fastening.

Proximal hub 3506 may include or rotate with respect to a bearing (notshown). The bearing may be seated in the distal end of broach sheath3508. Thus, when drive shaft 3510 rotates broaching member 3502, broachsheath 3508 and the bearing do not rotate. The orientation at whichproximal ends 3514 and 3516 of broaching member 3502 are fixed toproximal hub 3506 may provide or retain a shape of broaching member3502.

Distal hub 3504 may extend a distance E in the distal direction awayfrom distal portions 3518 and 3520 of broaching member 3502. Distal hub3504 may thus contact bone material inside bone B (shown in FIG. 2)before distal portions 3518 and 3520 contact the material. If thematerial is dense, such as cortical bone, the material may resist distaladvancement of distal hub 3504. Broaching member 3502 may thus beprevented from broaching or interacting with the material.

Distal hub 3504 may include flutes 3522 and 3524. Broaching edges 3526,3528, 3530, 3532, 3534 and 3536 may displace material inside bone B.Flutes 3522 and 3524 may intersect with each other at the distal end ofdistal hub 3504.

Distal hub 3504 may have a blunt distal end without flutes. This mayprevent broaching member 3502 from interacting with material thatresists distal advancement of distal hub 3504. The distal end of distalhub 3504 may be any suitable shape.

Distal hub 3504 may be absent from broaching head 3500.

FIG. 36 shows illustrative broach 3600. Broach 3600 may includebroaching head 3602, control shaft assembly 3604 and actuator 3606.

Broaching head 3602 may include linked blades 3608, 3610, 3612 and 3613.Linked blades 3608 and 3610 may have broaching edges 3630 and 3632,respectively. The broaching edges may broach bone inside bone B (shownin FIG. 2) when broach head 3602 is rotated about axis L_(I).

The blades may positioned radially by a locking mechanism. The bladesmay be positioned radially by a resilient mechanism such that the bladesmay interact with bone tissue with sufficient pressure to displace bonetissue of certain densities, but insufficient pressure to substantiallydisplace bones of a higher density.

Linked blades 3608, 3610, 3612 and 3613 may be linked by one or morelinkages such as linkages 3614, 3616, 3618 and 3620. Linkage 3618 (andcorresponding linkage 3619, not shown) may be supported by elongatedmembers such as fixed struts 3622 and 3624. Fixed struts 3622 and 3624may be fixed with respect to axis L_(I). Fixed struts 3622 and 3624 maybe joined by distal tip 3634.

Linkage 3614 may be supported by one or more elongated members, such aspull struts (not shown) that extend axially within control shaftassembly 3604. The pull struts may cause radial extension andcontraction of the blades by changing the axial distance between (a)linkage 3614 and (b) linkages 3618 and 3619 (not shown).

Control shaft assembly 3604 may include fixed struts 3622 and 3624, theone or more pull struts (not shown), housing members 3626 and 3628, oneor more filler members (not shown) and other suitable members (notshown).

Actuator 3606 may include elements for creating an offset betweenelongated members such as the fixed struts and the puller struts.Actuator 3606 may include elements for rotating broaching head 3602about axis L_(I).

FIG. 37 shows broaching head 3602 and a portion of control shaftassembly 3604 with housing members 3626 and 3628 removed. Pullers 3702and 3704 may be present in control shaft assembly 3604 to move linkage3614 axially relative to linkages 3618 and 3619.

FIG. 38 shows illustrative portion 3800 of linkage 3614. Portion 3800may be a pin channel that spans pull struts 3702 and 3704 and blades3608 and 3610. A pin (not shown) may traverse the pin channel to axiallyalign holes 3802, 3804, 3808 and 3810, of strut pull 3702, strut 3704,blade 3608 and blade 3610, respectively.

FIG. 39 shows pin channel 3902 of linkage 3618 and pin channel 3904 oflinkage 3619. Pin channel 3902 traverses blade 3612, housing member 3622and pin fastener 3906. Pin channel 3904 traverses blade 3613, housingmember 3624 and pin fastener 3908.

A pin (not shown) may be present in channel 3902 to axially fix linkage3618 to housing member 3622. A pin (not shown) may be present in channel3904 to axially fix linkage 3619 to housing member 3624. Linkages 3619and 3618 may be offset from axis L_(I) by offsets Δ₃ and Δ₄.

When broach head 3602 is rotated in bone B (shown in FIG. 2) indirection ω_(I) or −ω_(I), with blades 3608 and 3610 positioned asshown, broaching edges 3630 and 3632 (shown in FIG. 36) will sweep out aspace of radius R_(IMAX), which is the maximum radius for broach head3602. If linkage 3614 (shown in FIG. 36) were moved from the axialposition shown, broaching edges 3630 and 3632 would sweep out a space ofR_(I).

FIG. 40 shows the radial extent of tip 4002 of blade 3610 for differentaxial positions of linkage 3614. When linkage 3614 is in a most-proximalposition, tip 4002 may be at R_(I)=R_(I0). At R_(I0), broaching edge3622 may be disengaged from bone B (shown in FIG. 2). When linkage 3614is in an intermediate axial position, tip 4002 may be at R_(I)=R_(I1).At R_(I1), broaching edge 3622 may be engaged with bone B. AtR_(I)=R_(IMAX), broaching edge 3622 may be engaged with bone B at amaximum radius from axis L_(I).

Filler members such as filler 4004 may be placed in spaces between pullstruts. The filler members may be placed proximate blades that areactuated by the pull struts. The filler members may provide lateralstability to the pull struts.

FIG. 41 shows illustrative broaching head 4100. Broaching head 4100 mayinclude broaching members 4102. Each of broaching members 4102 may haveone or more features in common with broaching member 704 (shown in FIG.7) or any other broaching member shown or described herein. Broachinghead 4100 may have any suitable number of broaching members 4102. Forexample, broaching head 4100 may have one broaching member, 2-6broaching members, 7-20 broaching members, more than 20 broachingmembers or any suitable number of broaching members.

Broaching head 4100 may be contracted toward drive shaft 4110 andwithdrawn into a broach sheath (not shown). The broach sheath may beinserted in a hole such as H (shown in FIG. 2). Broaching head 4100 maythen be deployed by retracting the broach sheath. Broaching members 4102may be sufficiently resilient to be contracted and may expand away fromdrive shaft 4110 when the broach sheath is retracted.

Broaching members 4102 may include free distal ends such as distal end4104. Broaching members with free distal ends may be supported at theirproximal ends near the central axis of broaching head 4100.

Distal end 4104 may have any suitable shape, such as pointed, forked,rounded, blunt or truncated.

Broaching members 4102 may be supported proximally by one or more ofdrive shaft 4110, a proximal hub (not shown), and a broach sheath. Thebroach sheath may have one or more features in common with broach sheath127 (shown in FIG. 1).

Drive shaft 4110 may drive broaching head 4100 in rotation. The rotationmay be in direction ω_(s). The rotation may be in direction −ω_(s).Drive shaft 4110 may extend through the broach sheath (not shown) to aproximal rotation source (not shown).

Broaching members 4102 may be rotated at high angular speed to break upcancellous bone, such as bone B_(CA) (shown in FIG. 2). One or both ofstiffness of broaching members 4102 and angular speed may be chosen toselect a bone density threshold above which broaching members 4102 willhave reduced or substantially no effect and below which broachingmembers 4102 will break up the cancellous bone.

One or more of broaching members 4102 may include a spiral segment suchas 4106. Segment 4106 may be supported by one or more reinforcementssuch as 4108.

Segment 4106 may be rigid. Segment 4106 may be resilient. Segment 4106may have any suitable pre-set curvature. Segment 4106 may include asubstantially linear portion (not shown).

Segment 4106 may include a length of wire, ribbon, cable, stranded wire,or any other suitable form or structure. Segment 4106 may includepolymer, metal, alloy or any other suitable material. Segment 4106 maybe constructed of a mesh cut from metal tube.

Reinforcement 4108 may be a tube. A reinforcement 4108 may be formedfrom polymer, metal, alloy or any other suitable material. One or morereinforcements such as 4108 may be sized and positioned to supportsegment 4106 in a desired contour. One or more reinforcements such as4108 may provide bone-broaching abrasiveness, momentum or both.

Reinforcement 4108 may be a brace.

Spiral segment 4112 may “spiral” in the same direction as spiral segment4106. Spiral segment 4112 may “spiral” in the opposite direction fromspiral segment 4106 such that distal tips 4104 and 4114 “face” inopposite circumferential directions.

Broaching members 4102 may be absent from broaching head 4100.Reinforcements such as 4108 may be present in broaching head 4100 toperform as broaching members.

FIG. 42 shows illustrative intramedullary tool 4200. Tool 4200 mayinclude handle 4202, elongated support 4204 and probe 4206.

A practitioner may use handle 4202 to insert probe 4206 intointramedullary space IS of bone B (shown in FIG. 2). Probe 4206 may beused to determine the spatial distribution of cancellous bone B_(CA)(shown in FIG. 2) in intramedullary space IS. Probe 4206 may be used toapply force to a bone fragment such as fragments P_(h) and P_(a) (shownin FIG. 2) to position the bone fragment for provisional reduction of afracture such as F_(h) and F_(a) (shown in FIG. 2). Probe 4206 may beviewed in situ via fluoroscopic imagery or any other suitable type ofimagery during operation of tool 4200.

Probe 4206 may include distal face 4208. Distal face 4208 may berounded, conical, faceted or any other suitable shape. Probe 4206 mayinclude a wire loop.

Probe 4206 may include polymer, alloy or any other suitable material.

Elongated support 4204 may include one or more straight portions such asportion 4208. Elongated support 4204 may include one or more curvedportions such as portion 4210. Elongated support 4204 may be shaped suchthat probe 4206 may be inserted into an angled access hole such as H orI (shown in FIG. 2) and advanced substantially along bone axis LB towarddistal end D of bone B (shown in FIG. 2).

Elongated support 4204 may include one or more rigid sections. Elongatedsupport 4204 may include one or more flexible sections. A flexiblesection may help probe 4206 negotiate a turn from the angled access holeinto the intramedullary space. A flexible section may help probe 4206deflect away from high density bone, such as high density cancellousbone or cortical bone, during advancement substantially along bone axisL_(B) (shown in FIG. 2).

Elongated support 4204 may have one or more solid sections. Elongatedsupport 4204 may have one or more cannulated sections.

Elongated support 4204 may include polymer, alloy or any other suitablematerial.

Thus, apparatus and methods for fracture repair have been provided.Persons skilled in the art will appreciate that the present inventioncan be practiced by other than the described embodiments, which arepresented for purposes of illustration rather than of limitation. Thepresent invention is limited only by the claims that follow.

1. Apparatus for positioning a device relative to exterior features of a bone, the device having a portion that is configured to be positioned in a targeted region inside the bone, the bone having a surface, a surface normal axis, an anterior-posterior axis and a proximal-distal axis, the device comprising: a bottom index that provides alignment relative to the surface normal axis; first and second lateral extensions, the first lateral extension being configured to respond to an anterior contour of the bone, the second lateral extension being configured to respond to a posterior contour of the bone, the first and second lateral extensions providing alignment relative to the anterior-posterior axis; and a front index that has a distal end that is configured to provide visual alignment along the proximal-distal axis.
 2. A surgical instrument guide for guiding a surgical instrument relative to a bone, the surgical instrument guide comprising a set of members that operate exterior to the bone to position the surgical instrument at a location that is inside the bone, wherein the set of members includes: positioning members that position the guide on the bone with respect to displacement along three orthogonal rectilinear axes and with respect to rotation about the axes; and control members that retain the guide with respect to displacement along the axes and with respect to rotation about the axes.
 3. A method for performing a procedure in a bone interior, the method comprising: positioning an instrument template outside the bone interior at a position that corresponds to a target region inside the bone; generating an electronic image showing the instrument template and the target region; and delivering an instrument to the target region.
 4. The method of claim 3 wherein the delivering comprises arranging a guide member to direct the instrument to the target region, the guide member having a fixed orientation relative to the instrument template.
 5. An apparatus for guiding an instrument relative to an elongated bone having a longitudinal axis, the apparatus comprising: a instrument guide member; and a base member that supports the guide member; wherein the instrument guide member is configured to pivot with respect to the base from a first position defining a first angle relative to the longitudinal axis to a second position defining a second angle relative to the longitudinal axis.
 6. The apparatus of claim 5 further comprising an alignment template that registers the instrument guide member to a first target region inside the bone when the guide member is in the first position and to a second target region inside the bone when the guide member is in the second position.
 7. A method for broaching an interior region of a bone, the method comprising: expanding a bone broaching member in the interior region; disaggregating relatively low-density material inside the bone using the member; and deflecting the member away from relatively high-density material inside the bone.
 8. The method of claim 7 further comprising rotating the bone broaching member using a flexible drive shaft.
 9. The method of claim 7 in which the broach position is directable.
 10. The method of claim 7 wherein the disaggregating includes cutting the relatively low-density material.
 11. The method of claim 7 wherein the disaggregating includes displacing the relatively low-density material.
 12. The method of claim 7 further comprising: registering an exterior instrument guide to the bone broaching member; visually mapping the exterior instrument guide to the interior region; and deploying the bone broaching member to the interior region based on the exterior instrument guide.
 13. Apparatus for broaching a bone, the apparatus comprising: a rotator; and a broaching member fixed to the rotator and configured to be moved relative to the rotator to displace bone material that is radially away from the rotator.
 14. The apparatus of claim 13 wherein, when the bone material is first bone material, the broaching member is further configured to substantially deflect around second bone material, the second bone material having a higher density than the first bone material.
 15. The apparatus of claim 14 wherein the broaching member is configured to form in the bone a space having a first contour that corresponds to a shape of the broaching member and a second contour that corresponds to anatomy that includes the second bone material.
 16. The apparatus of claim 15 further comprising, when the broaching member is a first broaching member, a second broaching member disposed opposite the first broaching member.
 17. The apparatus of claim 13 wherein the broaching member includes a cutting edge.
 18. The apparatus of claim 13 wherein the broaching member includes a flexible wire segment.
 19. The apparatus of claim 18 wherein the wire segment includes braided wire.
 20. An apparatus for treating a bone interior, the apparatus comprising: a flexible sheath having a first configuration and a second configuration, the second configuration having a smaller radius of curvature than the first configuration; a rotatable shaft extending through the sheath; and an elongated steering member that is configured to deflect the flexible sheath from the first configuration to the second configuration.
 21. A bone interior preparation apparatus comprising an elongated member that is curved about a longitudinal axis and is configured to rotate about the axis inside a bone.
 22. A method for preparing a bone interior, the method comprising: providing access to a bone intramedullary space; introducing into the intramedullary space an elongated member having a substantially spiral segment having a longitudinal axis; and rotating the substantially spiral segment about the longitudinal axis to displace cancellous bone matter.
 23. A method for sawing a hole in a bone, the bone having a longitudinal axis, the method comprising: forming, along a direction that is at an acute angle to the longitudinal axis, a substantially cylindrical passage into the intramedullary space of a bone; and removing from the bone a substantially cylindrical plug that is substantially coaxial with the passage; and rotating the rotary coring saw or drill about a portion of the K-wire; wherein: the forming comprises tunneling through the bone using a K-wire; and the removing comprises sawing a hole using a rotary coring saw.
 24. The method of claim 23 further comprising sustaining a coaxial relationship between the K-wire and the rotary coring saw.
 25. The method of claim 24 wherein the sustaining comprises rotating the rotary coring saw or drill about a bushing, wherein the K-wire, the bushing and the rotary coring saw or drill are substantially coaxial.
 26. The method of claim 23 further comprising translating the K-wire relative to the rotary coring saw or drill to remove from the coring saw or drill the cylindrical plug.
 27. Apparatus for accessing the inside of a bone, the apparatus comprising: a rotatable saw or drill that includes a cannula; a bushing disposed in the cannula; and a wire that is disposed substantially coaxially with the rotatable saw or drill in the bushing.
 28. An assembly for accessing the inside of a bone, the assembly comprising a saw or drill, the saw or drill having a longitudinal axis and substantial windows or open areas along the axis, the windows helping to facilitate chip clearance, side cutting and reduced temperatures.
 29. Apparatus for preparing a bone interior, the apparatus having a longitudinal axis and comprising a first blade that is linked to a second blade by a linkage that is configured to be rotated about the longitudinal axis and radially displaced from the longitudinal axis.
 30. The apparatus of claim 29 wherein the mechanism is activated in a variable manner that limits amount of radial force mechanism can exert on the bone tissue
 31. A method for preparing a bone interior comprising: rotating a cutting surface inside a bone about a rotational axis; and moving a control member from a first control position to a second control position; wherein: the cutting surface is configured to occupy: a first radial position that corresponds to the first control position; a second radial position that corresponds to the second control position; and a third radial position that corresponds to an intermediate control position between the first and second control positions; and the third radial position is at a greater radial distance from the rotational axis than are both the first and second radial positions.
 32. A bone fragment positioning device comprising: a probe support having a proximal end and a distal end; a handle attached to the proximal end; and a probe attached to the distal end; wherein the probe support is configured to: traverse an angled access hole in a metaphyseal bone surface; and provide mechanical communication between the handle and the probe when the handle is outside a bone interior and the probe is inside the bone interior.
 33. A method for treating a bone, the bone having a longitudinal axis, the method comprising: providing a hole in the bone at an angle to the longitudinal axis, the hole providing access to a bone interior region; advancing a probe through the hole and into the interior region; and displacing cancellous bone using the probe.
 34. A method for treating a bone, the bone having a longitudinal axis, the method comprising: providing a hole in the bone at an angle to the longitudinal axis, the hole providing access to a bone interior region; advancing a probe through the hole and into the interior region; and displacing bone matter using the probe. 